Speaker 1: Brought to you by the reinvented two thousand twelve camera.
Speaker 1: It's ready. Are you get in touch with technology? With
Speaker 1: tech Stuff from how stuff dot com. Hello everyone, and
Speaker 1: welcome to tech stuff. My name is Chris Poulette and
Speaker 1: I'm an editor at how stuff works dot com. Sitting
Speaker 1: across from me is senior writer Jonathan. It was a bright,
Speaker 1: cold day in April and the clocks were striking thirteen.
Speaker 1: Take it. You're not doing songs anymore. No more songs,
Speaker 1: not movies. These are the first lines and novels. So
Speaker 1: if you know what novel that came from, let us know.
Speaker 1: That's a novel idea. It is. Uh. There was a
Speaker 1: second quote I almost used that was not a novel quote,
Speaker 1: but I almost use it, which is sixty k ought
Speaker 1: to be enough for anybody? A. Yeah, and that's uh.
Speaker 1: That apparently is not an accurate quotation, but at least
Speaker 1: he says it's not it's it's us. It's a possibly
Speaker 1: apocryphal quote from Mr Billy Gates. I feel like I've
Speaker 1: heard that name. So today we are but I can't remember,
Speaker 1: which is good because today we're going to be talking
Speaker 1: about memory, computer memory specifically. Yeah, and Uh, we had
Speaker 1: a lot of people request over over the length of
Speaker 1: tech stuff. Really the entire time we've been doing this,
Speaker 1: we have a lot of people ask us to do
Speaker 1: a podcast about RAM and to kind of talk about
Speaker 1: what RAM is, why you need it, and what does
Speaker 1: it do and how does it work? Which is funny
Speaker 1: because we kept not doing it because we thought we
Speaker 1: already had it. Turns out not so much. I did
Speaker 1: a search for the word RAM in our archives and
Speaker 1: UH saw a lot of programs, but not RAM. And
Speaker 1: I even search for memory. And the only memory thing
Speaker 1: we've done is we've talked about hard drives, which hard
Speaker 1: The relationship between hard drives and memory is a close one.
Speaker 1: It's an important one. And Uh. In fact, if we
Speaker 1: did not have RAM, if we if we had not
Speaker 1: developed that, and we were relying solely upon the kind
Speaker 1: of memory that you would find in a typical hard drive,
Speaker 1: you know, the traditional hard drive. Uh, computer operations would
Speaker 1: take much longer than what we're accustomed to. Yeah. As
Speaker 1: a matter of fact, I can, I can actually deliver
Speaker 1: a personal commentary on that because my very first machine
Speaker 1: was an Amiga one thousand. Uh. Many people have known
Speaker 1: because I mentioned it several times in the podcast, and
Speaker 1: that first machine that I had didn't have a hard
Speaker 1: drive on it. Um so Commodore's instructions. When you first
Speaker 1: turned the machine on, you would once it it got
Speaker 1: into boot up mode, you would see a copy of
Speaker 1: the Kickstart disc. Kickstart basically loaded the operating system uh
Speaker 1: into RAM, into random access memory, and then once that happened,
Speaker 1: you could launch your workbench, which is the equivalent of
Speaker 1: the desktop in what you would see in Windows Lennox
Speaker 1: or the Mac os today. UM So you know without
Speaker 1: that uh you know, when I got my first hard
Speaker 1: drive computer, which was an Amigia three thousand, UM, it
Speaker 1: had a forty megabyte Yeah, you can laugh at that
Speaker 1: hard drive which would automatically load the Kickstart and get
Speaker 1: everything started up for you. So it worked very much
Speaker 1: like our machines do now. But um you know that
Speaker 1: that was That's one of those things that that the
Speaker 1: hard drive takes care of that you didn't that you
Speaker 1: don't have to do, uh now, is load your operating
Speaker 1: system and all that stuff in there. There's also it's
Speaker 1: also important to note the difference between RAM and ROM.
Speaker 1: I would say read only memory or ROM. UM also
Speaker 1: has a lot of that baked into the chips onto
Speaker 1: your computer. There are some things that are already in
Speaker 1: your computer that are part of the UH UM the
Speaker 1: physical hardware. But and and read only memory UH That
Speaker 1: memory is at access sequentially rather than at random, which
Speaker 1: is how random access memory got its name right. And
Speaker 1: read only memory, as the name implies, you can only
Speaker 1: read from that memory. You can't write to it. So,
Speaker 1: in other words, it's unchanging. It is is static. It
Speaker 1: will always be the way it is, unless you were
Speaker 1: to physically remove the chips and replace them with other
Speaker 1: chips or other circuitry. It's always going to be the
Speaker 1: same way. And there's some devices that only have read
Speaker 1: only memory because that's all they require and it's important
Speaker 1: to have. It's UM. It's a very useful type of memory.
Speaker 1: But when you're working on a project, if you only
Speaker 1: had ROM and not RAM, you would have to burn
Speaker 1: a new ROM every time you wanted to save something
Speaker 1: to this it would be a real pain. So, for example,
Speaker 1: if you were to look at uh the good old
Speaker 1: video game console market, especially if you were looking at
Speaker 1: the old cartridge based consoles, the the games, the cartridges
Speaker 1: you have that you would put plug into your console
Speaker 1: had ROMs on them. That was the game itself was
Speaker 1: a ROM. And that's why if you talk about things
Speaker 1: like the main emulator, and I know that's it's kind
Speaker 1: of like saying a t M machine, but the emulator
Speaker 1: for arcade machines UH that you can run on certain computers.
Speaker 1: The emulator's job is to to mimic the circuitry that
Speaker 1: you would find within an arcade machine to run a
Speaker 1: specific ROM or game. So ROMs are used in devices,
Speaker 1: and in some cases are are the only thing within
Speaker 1: that device. There might be some other memory there to
Speaker 1: do things that keep track of a high score. That's
Speaker 1: a little different, but but in general, um, you know,
Speaker 1: there are certain devices that will only have ROM. RAM, however,
Speaker 1: is very important for the way we use computers today.
Speaker 1: Think of RAM as it's a it's a temporary storage
Speaker 1: facility for a computer, right. So it's where you can
Speaker 1: temporarily store instructions and data so that your computer processor
Speaker 1: doesn't have to go hunting through your hard drive system
Speaker 1: in order to find the relevant information to execute a command. Um.
Speaker 1: The way I like to think about this is if
Speaker 1: you're a student, imagine that you have a textbook filled
Speaker 1: with facts will say physics. It's a physics textbook, all right,
Speaker 1: and you've got a test coming up, and you've created
Speaker 1: a crib sheet for you to study from, and the
Speaker 1: crib sheet has bulleted points on it about the major
Speaker 1: things you're going to be covering in your next physics test.
Speaker 1: That crip sheet is kind of like RAM in the
Speaker 1: sense that you can make little notes, you can erase stuff,
Speaker 1: you can replace things, and it has a good instruction
Speaker 1: set for you to work from. Now, occasionally you might
Speaker 1: come across a problem. Let's say you're working on some
Speaker 1: homework that's going to prepare you for this test, and
Speaker 1: you've got your crib sheet in front of you and
Speaker 1: you're working on your homework question, and you realize that
Speaker 1: the information that you need is not on the crib sheet.
Speaker 1: It's just doesn't go that deep. So you have to
Speaker 1: go to the text book to refer to the right
Speaker 1: section to learn the stuff you need in order to
Speaker 1: answer that question. That's kind of like your computer. Your
Speaker 1: CPU is going to refer back to the memory to
Speaker 1: see if the information it needs is there, and if
Speaker 1: it's if the information goes beyond that little memory, if
Speaker 1: it's something that has to actually access the hard drive,
Speaker 1: it will go to the hard drive, same sort of idea. Yeah,
Speaker 1: and um, I would just like to note that when
Speaker 1: I said that RUM could only be access sequentially, that's wrong.
Speaker 1: I was actually thinking of serial access memory or SAM.
Speaker 1: I apologize for that. Yeah, I haven't had enough coffee
Speaker 1: this morning apparently, But yeah, cereal access memory is uh,
Speaker 1: is another form of memory that's not used nearly as
Speaker 1: often today as it used to be. But back when
Speaker 1: we had tape drives, Um, you know, you used to
Speaker 1: have to go all the way through the tape until
Speaker 1: you got to the part where it had the information
Speaker 1: you needed, letter than accessing it. It's just the same
Speaker 1: as if he's had a cassette tape, right, had an
Speaker 1: old cassette tape with music on it, and you wanted
Speaker 1: to listen to a specific song. You had to fast
Speaker 1: forward or play through the tape until you got to
Speaker 1: the song you wanted, and then you could listen to it.
Speaker 1: You couldn't just jump right to the song. For our
Speaker 1: younger listeners, this might seem like a completely foreign concept,
Speaker 1: but yes, uh, lots of us used to listen to
Speaker 1: cassette tapes and if you were really lucky you had
Speaker 1: like the eight track tapes where your options were even
Speaker 1: more limited in order to navigate to the next song. Yes,
Speaker 1: but ROM doesn't necessarily work that way, so I apologize
Speaker 1: for that. But random access memory there, there's certain there
Speaker 1: are different kinds of it. One of the most common
Speaker 1: is dynamic RAM. Yeah, that's that's probably the most versions
Speaker 1: of that are probably the most common used in computers today. Yeah,
Speaker 1: and uh. And the way that random access memory, dynamic
Speaker 1: random access memory is is arranged is that you can
Speaker 1: imagine a grid, right, and the the columns there are
Speaker 1: columns in their rows, and where these intersect, you have
Speaker 1: memory cells. Now, a memory cell, the most basic memory
Speaker 1: cell is essentially a transistor and a capacitor, and the
Speaker 1: capacitor can hold a charge. If the capacitor is holding
Speaker 1: a charge, the memory cell is registering as a one.
Speaker 1: If the capacitor is not holding a charge, it's registering
Speaker 1: as a zero. The transistor access a switch that allows
Speaker 1: the various things. It allows the computer to be able
Speaker 1: to read those particular cells and also to recharge those cells.
Speaker 1: Because here's the thing about capacitors, they do drain. Yeah,
Speaker 1: they can hold a charge. There they're sort of like
Speaker 1: a battery, though they are not identical, so don't assume
Speaker 1: that that's the same thing, but they're they fulfill similar functions.
Speaker 1: Capacitors usually release their energy in a burst as opposed
Speaker 1: to over a prolonged time. But yeah, the capacitors. The
Speaker 1: the energy drains from the capacitors, so they have to
Speaker 1: be recharged regularly and rapidly in order for them to
Speaker 1: maintain that charge and hold onto what we call a state. Yes,
Speaker 1: the state of that memory cell. So the state is
Speaker 1: either a one or a zero. If it's a one,
Speaker 1: the computer has to continually send energy to that uh
Speaker 1: sell in order for it to maintain a one until
Speaker 1: the memory needs to be written over, in which case
Speaker 1: it might be a one again or it might be
Speaker 1: a zero. It all depends on what the information is.
Speaker 1: And you've got the like I said, you've got columns
Speaker 1: and you've got rows, and uh the way the computer works,
Speaker 1: it has all these different little um components to it
Speaker 1: that will detect what the current state is of all
Speaker 1: those different memory cells in order to be able to
Speaker 1: uh to to pull the right information. And in fact,
Speaker 1: the computer keeps a record of which memory sell it
Speaker 1: needs to go to because you can think of the
Speaker 1: intersection of that column in that row as an address. Yeah,
Speaker 1: if you think about it as a piece of graph paper, Yeah,
Speaker 1: kind of the computer just basically keeps track of, uh,
Speaker 1: you know, where each item is in that memory. Yeah.
Speaker 1: If you think of the columns is like things like A, B, C, D, E, F. No,
Speaker 1: sort of like think of it kind of like a
Speaker 1: game of battleship. That's exactly what I was thinking. Yeah,
Speaker 1: you got that. You've got the columns that are maybe
Speaker 1: A through Z, and then you have one through twenty
Speaker 1: six as the rose, and you want to look at
Speaker 1: A four. Well, then you know exactly where to go
Speaker 1: to to pull up that information. You don't have to
Speaker 1: you don't have to go through the entire sequence of
Speaker 1: memory cells in order to get at that information. That's
Speaker 1: a very simplistic way of saying what is happening with
Speaker 1: this dynamic random access memory. One of the disadvantages here, though,
Speaker 1: is that having to refresh that memory constantly means that
Speaker 1: you're essentially slowing down the memory um, which is you know,
Speaker 1: a problem. It's it's something that that requires a lot
Speaker 1: of energy. It requires, uh that you're constant, constantly refreshing
Speaker 1: it and slows down your memory. Now, UM, having more
Speaker 1: memory in your computer is a good thing. UM. You
Speaker 1: know remember when we talked about thirty two bit and
Speaker 1: sixty four bit systems. Um. You know, your your operating
Speaker 1: system and your computer, depending on how they work together,
Speaker 1: can address a certain amount of computer memory. UM. And
Speaker 1: uh you know with if you have if you are
Speaker 1: not taking advantage of the maximum capacity of memory or
Speaker 1: at least you know, as much as your computer can hold. UM,
Speaker 1: not only is it having to uh fit whatever programs
Speaker 1: you're trying to run on top of the operating system
Speaker 1: in that amount of memory, it's also dealing with uh
Speaker 1: constantly having to refresh that memory. So it can really
Speaker 1: slow your computer down. Going back to the grid really quickly.
Speaker 1: The the columns along this grid are called bit lines,
Speaker 1: the rows are called word lines, and then a the
Speaker 1: intersection is the memory cell address. So uh, the what
Speaker 1: when you are wanting when you want to write information
Speaker 1: or when your computer needs to write information to your
Speaker 1: RAM in order for the CPU to be able to
Speaker 1: have access to it to make things run smoothly. First
Speaker 1: it starts sending electricity through the column area, so through
Speaker 1: the bitline um individual bitline, and then the computer sends
Speaker 1: electricity through the appropriate wordlines the right rose. So let's
Speaker 1: say that you you know that you're you're you're activating
Speaker 1: column D that's the one that's being um that electricity
Speaker 1: is running through right now. And you know that Rose five, twelve,
Speaker 1: and twenty three need to have need to be activated
Speaker 1: because those memories, the memory cells at those addresses at
Speaker 1: the intersection of column d uh need to be active
Speaker 1: in order for the information to be there. The computer
Speaker 1: sends this information, the transistor allows the capacity turns to
Speaker 1: take on that that charge, and then there's a little
Speaker 1: um sensor actually since amplifier as well, that receives the
Speaker 1: signal that says this capacitor has has a state of one,
Speaker 1: and that's what allows the computer no, you know if
Speaker 1: it's a one or zero, and collectively all those ones
Speaker 1: and zeros give it the information it needs. Now, all
Speaker 1: of this happens in a manner of a few nanoseconds,
Speaker 1: So don't think like this is taking ages. It's it's
Speaker 1: it's billions of a second for this stuff. When I'd
Speaker 1: say slow, I would put that in quote it right slow,
Speaker 1: like the way we feel when we put something in
Speaker 1: the microwave for a minute and we're thinking, why isn't
Speaker 1: it done yet? That kind of slow. Yes, it's not slow,
Speaker 1: as in, you put something in the oven and four
Speaker 1: days later you've got turkey. Uh the I put an
Speaker 1: old boot in there. There's a turkey. That's the way
Speaker 1: it worked, isn't it. No? Oh, I need to go
Speaker 1: home after this podcast. But at least I'll have some
Speaker 1: warm boots. Uh. Yeah. So this this is all taking
Speaker 1: just nanoseconds for each individual transaction, melal seconds for the
Speaker 1: whole thing. So, but it's happening repeatedly until that memory
Speaker 1: is getting rewritten. And it's happening. You know, it's changing
Speaker 1: rapidly because that's the nature of memory. If you're running
Speaker 1: a lot of different applications and uh, your memory might
Speaker 1: be filling up pretty quickly with all this information. That's
Speaker 1: why the more applications you run, if you're if you're
Speaker 1: using an older machine and you're running a lot of
Speaker 1: different applications, you might feel like you're everything's kind of sluggish.
Speaker 1: And that's why people will tell you like, oh, well,
Speaker 1: you need to close some of these applications because it's
Speaker 1: taking up space. In the memory, and the CPU is
Speaker 1: having to work harder to get the information it needs
Speaker 1: to act to execute your hands. So, uh, you know
Speaker 1: that that's how that all plays in. That's why people say, oh,
Speaker 1: if you want a computer to go faster, you need
Speaker 1: more memory, because then you can you can actually run
Speaker 1: more applications. That tends to be a very common problem
Speaker 1: that people run into, right that they're like, my computer
Speaker 1: is so slow, and you look at and you're like, well,
Speaker 1: you've got fifteen applications open, and three of them are
Speaker 1: pretty heavy duty, um, you know, or graphics intensive or whatever,
Speaker 1: something that's going to require a lot of processing. That
Speaker 1: would be why it's both processor speed and the amount
Speaker 1: of memory you have. The two are very much important.
Speaker 1: And also when we talk about Moore's law, More's law
Speaker 1: plays into the into memory as well, because dynamic random
Speaker 1: access memory, the nice thing about it is that, well
Speaker 1: two nice things about is that it's relatively inexpensive and
Speaker 1: it doesn't take up a lot of physical space when
Speaker 1: you're designing memory chips. There are other types of random
Speaker 1: access memory, not just dynamic. Their static random access memory.
Speaker 1: And static random access memory uses uh something a logic
Speaker 1: construction called a flip flop, Yes, not a sandal. I
Speaker 1: was gonna say, you're gonna and it comes out as
Speaker 1: chicken already know that doesn't work well. The static random
Speaker 1: access memory, um, yeah, I mean it one of the
Speaker 1: benefits of eas now flip flops. Actually we uh, you
Speaker 1: go back to the Boolean logic um reference. But basically
Speaker 1: a static RAM has the benefit of being a lot
Speaker 1: faster than dynamic RAM. Well, for one thing, what it does,
Speaker 1: once it has a state, it will hold that state
Speaker 1: until you tell it to change, So it doesn't In
Speaker 1: other words, it doesn't it doesn't require to be recharged,
Speaker 1: doesn't have a capacitor that is leaking energy and has
Speaker 1: to be refilled. So once you once you set a
Speaker 1: flip flop to one, it's gonna stay a one till
Speaker 1: you tell it to be a zero. So that sounds great.
Speaker 1: Why don't we use static RAM instead of dynamic RAM
Speaker 1: for our you know, main RAM and our computers. Two reasons. One,
Speaker 1: it takes up more space, so you end up having
Speaker 1: problems like especially with things like mobile devices or or
Speaker 1: laptop computers. You start running into the problem of while
Speaker 1: you can only fit so much into a form factor
Speaker 1: before he gets clunky, right, right, You need more transistors
Speaker 1: for static RAM. Yeah, yeah, four to six for each
Speaker 1: flip flop. So that's and each flip flop is is
Speaker 1: representing one memory cell. So and granted, these transistors that
Speaker 1: we're talking about are on the nano scale at this point,
Speaker 1: you know, we're talking about tiny, tiny, tiny transistors. But
Speaker 1: even so those add up if you need to have
Speaker 1: the amount of memory that you're accustomed to. So they
Speaker 1: are they take up more space, and they're more much
Speaker 1: more expensive. So static RAM is not something you're gonna
Speaker 1: find in every single kind of device, although as you know,
Speaker 1: as the technology has improved, those prices do tend to
Speaker 1: go down, so we do see more and more of that,
Speaker 1: but dynamic RAM is still probably i would say, the
Speaker 1: most popular by far. Um. There there's another potential change
Speaker 1: coming up, a new development that could really uh impact this,
Speaker 1: which we can get into in a little bit. Okay, Yeah,
Speaker 1: I was gonna mention too though, that that static RAM
Speaker 1: can be found in your computer, probably because um, if
Speaker 1: you've seen a list of computer specifications, perhaps when you're
Speaker 1: shopping for a new machine and you see the cash
Speaker 1: referred to, um, your computer's cash is uh, probably static RAM. Yeah,
Speaker 1: a lot of CPUs have this built in. Uh, A
Speaker 1: lot of the ones that use multi threading, that have
Speaker 1: multi core processors. A lot of these CPUs have their
Speaker 1: own sections of memory built And it's not it's not
Speaker 1: your computer's RAM, it's something that's specifically part of the
Speaker 1: CPU chip set that is there to help make make
Speaker 1: those those data transfers even faster, so that it makes
Speaker 1: it very efficient. And for the the most commonly used commands, uh,
Speaker 1: those would be stored within the cash. So in that
Speaker 1: crib sheet example I gave, let's say that you even
Speaker 1: had a little note card next year, a crib sheet
Speaker 1: that had the four formulas you're going to use them
Speaker 1: most frequently in that physics test, and so you've got
Speaker 1: those there because this way, no matter what you know,
Speaker 1: you just have to glance at the at the note
Speaker 1: card and like, that's that's the formula I need. And
Speaker 1: you plug it in and you make it, you make
Speaker 1: it work and whatever. The problem is. Your CPU is
Speaker 1: really really good at executing operations upon data, but it's
Speaker 1: stupid in the sense that as soon as it's as
Speaker 1: soon as it's finished doing that, it's forgotten. There's no, yeah,
Speaker 1: it has no memory of its own other than this
Speaker 1: this cash that we're talking about. A CPU on its
Speaker 1: the very basic CPU has no memory, so it can
Speaker 1: do stuff, but as soon as the task is done,
Speaker 1: it's like a blank slate all over again. That's that's
Speaker 1: why we have to have memory in order to get
Speaker 1: this to work. If if the CPU could somehow remember
Speaker 1: on its own, then you'd have other issues like, well,
Speaker 1: now you needed to do something new, So how do
Speaker 1: you write over what you had before? Do you just
Speaker 1: add to it? If you add to it, how long
Speaker 1: until you reach capacity? And you can't do anything with
Speaker 1: that CPU other than the stuff that you've already done.
Speaker 1: So you know, this is why the whole idea of
Speaker 1: the random actis memory that could be rewritten very quickly
Speaker 1: was so important, because otherwise you limit the functions that
Speaker 1: your computer is capable of doing. You know, there was
Speaker 1: this computer is great at adding and subtracting and dividing,
Speaker 1: and after that you can't do anything else because that's
Speaker 1: I was about to install Pacman, but darn it, I
Speaker 1: already took up all of its space with these three functions. Well, yeah,
Speaker 1: so you've got uh and and we're we're sort of
Speaker 1: filling out the whole computer. So you've got your your CPU,
Speaker 1: and you've got a CASH to help it remember stuff
Speaker 1: that it needs to do basic operations. And then you've
Speaker 1: got your your memory, your RAM, your dynamic RAM that
Speaker 1: that's over here managing the stuff that you've got going on,
Speaker 1: your your word pressing, your word uh processor uh stuff,
Speaker 1: and your your graphics program, the stuff that you have
Speaker 1: your browser, your your email program. But you also have
Speaker 1: uh in your modern computer, you've got your graphics processor
Speaker 1: chip and in a lot of cases, UM, and I'm
Speaker 1: I'm just hedging my bets here that somebody has some
Speaker 1: weird computer that doesn't have this also has its own
Speaker 1: RAM UM to help it pro specifically process graphics. UM.
Speaker 1: So that RAM in general is off limits to the
Speaker 1: rest of the machine because it's saying no, no, no no.
Speaker 1: This memory is specifically to help us render graphic on
Speaker 1: the screen so that the user can uh see everything
Speaker 1: that he or she wants to see from the other programs.
Speaker 1: So it's not handling programs, it's handling graphics. We have
Speaker 1: we have seen some processors recently that are able to
Speaker 1: tap into the graphics processing units as well. And be
Speaker 1: able to uh to utilize those two process particularly difficult
Speaker 1: problems or powerful, you know, time consuming problems to try
Speaker 1: and reduce the amount of time it takes to get
Speaker 1: through that application. So and in fact, we're seeing we're
Speaker 1: seeing both sides, right. We're seeing UH CPU manufacturers get
Speaker 1: into adding in elements that specifically tackle graphics processing, and
Speaker 1: we've seen graphics processing unit manufacturers get into handling more
Speaker 1: basic processing UH functions. So the two worlds have been
Speaker 1: colliding for probably us well for for quite a quite
Speaker 1: a while, but really visibly for the last two years. Yeah,
Speaker 1: I'm thinking specifically of Apple's Grand Central Technology, one of
Speaker 1: those things in snow Leopard that people didn't really care about,
Speaker 1: but it was actually supposed to improve the operating system,
Speaker 1: but it was mainly thinking of Intel Sandy Bridge, which
Speaker 1: had its own graphics processing element added into it. And
Speaker 1: the thing is that, uh so that so the rule
Speaker 1: that we were just talking about is is going to
Speaker 1: be shifting as time goes on, and UH processor manufacturers
Speaker 1: of all kinds are more sophisticated, the operating systems become
Speaker 1: more sophisticated and able to take advantage of these changes. UM.
Speaker 1: But that's kind of the way it works out. And
Speaker 1: I just wanted to illustrate the fact that RAM can
Speaker 1: be used to support a number of computer functions. You'll
Speaker 1: also see it in you know, all kinds of other
Speaker 1: devices that use memory, cameras, um cars, all kinds of
Speaker 1: technologies that use comput you are processing that you may
Speaker 1: or may not necessarily think of as having computers inside,
Speaker 1: but you know they have some form of RAM in there. Now.
Speaker 1: Of course, RAM has gotten more sophisticated itself over time too.
Speaker 1: And you do you want to talk about some of
Speaker 1: the older types or do you want to talk about
Speaker 1: the improvements you were just about to mention, Well, um,
Speaker 1: I have something leading up into the improvements. If you have,
Speaker 1: if you have information about older types of memory, I'd
Speaker 1: more than happy to hear it. I personally did not
Speaker 1: research that, so I have none of that information in
Speaker 1: front of me. Okay, all right, well, um, I have
Speaker 1: some of it. And and really this could probably get
Speaker 1: kind of dry, um, but basically, you know, as as
Speaker 1: time has gone on, you've been able to see you
Speaker 1: were talking about Moore's law, which of course says that
Speaker 1: the number of transistors on a processor chip will double
Speaker 1: in well, originally it was two years now half or wait,
Speaker 1: I'm sorry, that's backwards. Yeah, it tends to go back
Speaker 1: and forth between twelve months to twenty four months and
Speaker 1: eighteen to twenty four tends to be the most frequently
Speaker 1: cited figures. So depending on any given year, you'll hear, oh, well,
Speaker 1: it's one of the things that the Moore's law gets
Speaker 1: gets validated in retrospect, right, because you have to look
Speaker 1: back two years ago and look and see how many
Speaker 1: transistors were found on a CPU, or like we're staying
Speaker 1: here a memory circuit. That also can apply. If you
Speaker 1: can fit twice as many transistors in the memory circuit,
Speaker 1: then that's another example of Moore's law holding true. M Um,
Speaker 1: but yeah, basically, as far as the memory chips have gone,
Speaker 1: there's been a wave of advances over the last couple
Speaker 1: of decades in which more and more processors are are added.
Speaker 1: The way that their accesses has changed. I remember with
Speaker 1: my Amiga three thousand they used a very unusual type
Speaker 1: of memory called zips, in which the pins that you
Speaker 1: use to plug them in were basically a zig zag.
Speaker 1: There was a pin on one side, then there was
Speaker 1: one on the other side, there was one on the
Speaker 1: other side, you know, and flipped back and forth between them.
Speaker 1: Only a very few computers used that type of technology. UM.
Speaker 1: When I got a Mac, it used sims UM, which
Speaker 1: is a single inline memory module. UM. You can actually
Speaker 1: find quite a bit about the different types of memory
Speaker 1: on We referred to it in our how ram works
Speaker 1: article on how stuff works dot com, but it's on
Speaker 1: Kingston's website and it's UM. You know, it talks about
Speaker 1: the different types. But the single inline modules were an
Speaker 1: improvement over that the older technology, and then they came
Speaker 1: out with a dual inline memory modules UM, and they
Speaker 1: basically it's a little itty bitty card UM. It's long, UM,
Speaker 1: but it has a series of chips soldered into it UM.
Speaker 1: And those are the memory chips, right. And the old
Speaker 1: days you actually had to install a memory chip directly
Speaker 1: into the motherboard. Yeah, this is the This sort of
Speaker 1: predates the more I would say, the nine needs in
Speaker 1: two thousands computers. This is like the old four right,
Speaker 1: So if you want to upgrade your computer, it actually
Speaker 1: meant opening up your computer, disconnecting the motherboard, and then
Speaker 1: possibly UM, depending on how the memory chip was designed,
Speaker 1: you might even have to do some soldering. But but
Speaker 1: you know, install a new memory chip so that your
Speaker 1: computer would have more memory. Eventually, improvements included, uh designing
Speaker 1: something called a memory bank where you had a port
Speaker 1: essentially that you could plug in a card that had
Speaker 1: a certain number of memory chips of a certain capacity,
Speaker 1: and then as technology improved, you could replace that card
Speaker 1: with a card that had a greater capacity. Now, keep
Speaker 1: in mind that your computer CPU would determine how much
Speaker 1: memory your computer could actually use. There would you would
Speaker 1: reach a point where it wouldn't matter if you could
Speaker 1: buy a card with more memory, your CPU wouldn't be
Speaker 1: able to access it. Yeah, it had had limitation on that,
Speaker 1: So there were you know, you that's why if you
Speaker 1: were to look at computer specs and see like, you know,
Speaker 1: upgradeable up to whatever, that's the reason why is that
Speaker 1: the CPU itself has that limitation and so um, you
Speaker 1: know something. You know, in America at least, we have
Speaker 1: this philosophy of more is better. But there's a certain
Speaker 1: point where, depending on the machine you're using, more isn't
Speaker 1: going to do you any good because your computer simply
Speaker 1: cannot use it. Yeah, and that's actually sort of the
Speaker 1: source of Jonathan's earlier quote, UM, I just the idea
Speaker 1: behind it is that you know, there's only so much
Speaker 1: you can use. UM DEM's actually had chips on both
Speaker 1: sides of that UH circuit board, and we're able to
Speaker 1: handle more memory and more quickly. And you know, from
Speaker 1: there we've moved UM move forward. I won't get into
Speaker 1: to all of it, but we really got into the
Speaker 1: more advance it's types of memory in the two thousands
Speaker 1: when we got into UM UH the UM dynamic RAM
Speaker 1: and that that made things a lot more And basically
Speaker 1: what they've done is, over the period of time, made
Speaker 1: the transfer of information more efficient. They've increased the number
Speaker 1: of transistors and the amount of information that could be
Speaker 1: stored on a single UH card with the RAM in it.
Speaker 1: And it's just it's just done. Some made some insignificant
Speaker 1: improvements over the past few years. Right. And and memory
Speaker 1: relies on something called a memory controller. Yes, that's part
Speaker 1: of what maintains like it determines UH when to write
Speaker 1: two memory cells. It also helps read the memory cells.
Speaker 1: It's it's kind of like a manager, right, But it
Speaker 1: also has to check the memory whenever it's getting information
Speaker 1: back from memory, has to check it for errors. And
Speaker 1: depending on what kind of system you're using, you might
Speaker 1: have a memory chip with just with a built in
Speaker 1: error checking technology which is called a parody check, so
Speaker 1: checking for parody to make sure that the information it's
Speaker 1: it's delivering is accurate. Um. There are a lot of
Speaker 1: different ways of doing this, but one is So we
Speaker 1: talked about information in in the computer world in terms
Speaker 1: of bits and bytes, right, and a bite is eight bits,
Speaker 1: which kind of represent a unit of information of useful
Speaker 1: information because each bit is itself a unit of information,
Speaker 1: but in order for it to be useful for a computer,
Speaker 1: we we group them in groups of eight uh. Standard.
Speaker 1: Now that wasn't when computers first were developed. There were
Speaker 1: several different competing Um. I guess you could calm standards
Speaker 1: because they were standard amongst a certain group of computers.
Speaker 1: But we kind of selled on this whole eight bit
Speaker 1: is a byte model and with parity, they there's an
Speaker 1: extra bit added on to the end and uh that
Speaker 1: bit is um it's kind of a marker, right, Yeah,
Speaker 1: it's basically used for error checking. Yeah. So if if
Speaker 1: the uh, for example, it looks at how many of
Speaker 1: the bits within that bite are ones versus zeros. So
Speaker 1: if all of the if there are an odd number
Speaker 1: of ones in that byte, remember it's eight bits, there's
Speaker 1: an odd number, the parity bit is set to one.
Speaker 1: If it's an even number, the parody bit is set
Speaker 1: to zero. So then when the data is being processed,
Speaker 1: the totals added up again and it's checked against the
Speaker 1: parody bit. Now, if that matches, the assumption is that
Speaker 1: the that byte is correct, it's accurate, and everything's cool.
Speaker 1: If it comes up as a conflict, then that's a
Speaker 1: message to say, dump this information because something has gone wrong. Now,
Speaker 1: the parody bit does not tell you what the information is.
Speaker 1: It just is a shorthand way of saying, all right,
Speaker 1: are there an even number of ones in this byte? Yes, well,
Speaker 1: then something's gone wrong. It doesn't tell you what the
Speaker 1: information is or why it's wrong. It just says that's
Speaker 1: not what I got when I added it up, right,
Speaker 1: So uh. And then there's that that's called even parody.
Speaker 1: That's that particular model. That's just one way of doing it.
Speaker 1: There's also odd parody, which is kind of the same idea,
Speaker 1: except you know, if it's an odd number of ones,
Speaker 1: then it's considered a zero of it's an even number
Speaker 1: of ones, it's considered a one. But uh, there's also
Speaker 1: the error correction code method, which goes a little bit further.
Speaker 1: This is this is so you've got parody that tells
Speaker 1: you there's a problem. Error correction is to try and
Speaker 1: step in when there's a problem and fix it. Um.
Speaker 1: It uses additional bits to monitor the information that the
Speaker 1: actual information that's in the byte, so it's looking at
Speaker 1: the information itself, not just a summary UM. And it
Speaker 1: uses pretty complicated algorithms to try and head off any problems.
Speaker 1: So there, you know, this has to be built in
Speaker 1: because occasionally things go wrong. Sometimes something doesn't trip when
Speaker 1: it's supposed to trip, and uh, your CPU doesn't necessarily
Speaker 1: know that. You know, CPU is just working on what's
Speaker 1: given to it. So again, since the CPU can't remember
Speaker 1: what it did last in its last nanosecond, it's just saying,
Speaker 1: all right, I gotta execute this particular operation against this
Speaker 1: particular set of information. It doesn't know or care if
Speaker 1: it's the correct operation or information set. So you have
Speaker 1: to have that error correction in. There's in some places.
Speaker 1: It's not always in the memory controller chip. Sometimes it's
Speaker 1: part of the CPU. It's it all depends on the
Speaker 1: architecture of the computer system itself. Yeah. Now, um, it's
Speaker 1: also important to note, um uh that as memory uh
Speaker 1: improvements have changed, the way of of doing this has changed.
Speaker 1: And of course that probably the the type of RAM
Speaker 1: that you have in your computer, if you've got a
Speaker 1: more recent UH computer, is the aversion of the double
Speaker 1: data rate synchronous d RAM dynamic RAM or U d
Speaker 1: d R and you know d d R two d
Speaker 1: d R three um s d RAM. But that's uh,
Speaker 1: you know, that's changing. As you were saying, their improvements
Speaker 1: being made. I know, one of the types of memory
Speaker 1: that people have been talking about is magnetic RAM, which
Speaker 1: is supposed to basically give you an instant on some
Speaker 1: uh situation when you turn your computer on, because uh
Speaker 1: it can store the information and pull it up immediately
Speaker 1: and you don't have to worry about a long boot
Speaker 1: up sequence as the RAM is getting uh populated with information, right. Yeah.
Speaker 1: The idea here is to have something some sort of
Speaker 1: system in place that can maintain a state without the
Speaker 1: need for uh the electrical impulse to go through and
Speaker 1: boot it up. Right. So another potential solution, although this
Speaker 1: is one that is still being developed is the memorister. Yes, memoristers.
Speaker 1: These are interesting things. Uh, it's kind of difficult. It's
Speaker 1: really complicated to to get into detail. But from a
Speaker 1: bird's eye perspective, a memorister is an electrical component, all right.
Speaker 1: And if you run current through a memorister in one direction,
Speaker 1: the electrical resistance increases. If you run current through the
Speaker 1: opposite way, the resistance decreases. Now, once the current stops
Speaker 1: moving through, the memorister holds onto whatever the last resistance was.
Speaker 1: So if you ran it through the first way, then
Speaker 1: the resistance has been is stays at its increased level.
Speaker 1: If you if you last ran it through the opposite way,
Speaker 1: then it's going to be at its decreased level. Well,
Speaker 1: that's that's a two bit system, right. You could assign
Speaker 1: one of those a one and the other one of
Speaker 1: zero and once you ran through that once, uh, it
Speaker 1: would make it would hold on to that information. And
Speaker 1: it takes up much less space than the typical memory
Speaker 1: transistors do, so it's smaller and it will hold on
Speaker 1: to whatever the state is until you tell it that
Speaker 1: you know you want to change by by and you
Speaker 1: tell it by running the electricity through it one way
Speaker 1: or versus the other. Does the computer have to remain
Speaker 1: plugged in for this to work. No, once you've once
Speaker 1: you've done it, once you've run the current through, you
Speaker 1: can turn the current off and the memorister retains that resistance.
Speaker 1: So the only thing that has to happen is the
Speaker 1: computer has to be able to detect what the resistance
Speaker 1: is of that memory rister. So once it detects what
Speaker 1: the state is, then you've got that information already there.
Speaker 1: So it could be used in various kinds of processors
Speaker 1: as well as memory. And because it's smaller, you could
Speaker 1: at least potentially cram far more memory into a smaller
Speaker 1: space than what is capable using right now through transistors.
Speaker 1: So this is this is a potential way to keep
Speaker 1: Moore's law going. In fact, if the developments were to
Speaker 1: progress at a at a good clip, we could almost
Speaker 1: leap frog quite a bit because the potential is that
Speaker 1: it would revolutionize UH processing and memory all in a
Speaker 1: in a a fell swoop, a swell foop. Yeah. Now
Speaker 1: I'm not sure that the board would agree. I'm sure
Speaker 1: that they say that anything involving resistance, Yeah, but yeah,
Speaker 1: it's it's an interesting idea, and it's something that's was
Speaker 1: first proposed back in nineteen seven. Any one and UH
Speaker 1: and HP Labs has been working on it diligently. UM
Speaker 1: and in fact, in two thousand and eight announced that
Speaker 1: it was developing switching mem risters. So these are these
Speaker 1: are the sort of technologies that I think are going
Speaker 1: to become far more important in the near future. Because
Speaker 1: again we've talked about this before about how the world
Speaker 1: is moving to mobile devices literally in some cases, but
Speaker 1: that mobile devices are becoming increasingly important. Well, with a
Speaker 1: mobile device, you have a much more limited amount of
Speaker 1: space that you have to work within, and so something
Speaker 1: like a memrister, which could at least, at least in theory,
Speaker 1: pack much larger punch and a much smaller package. It
Speaker 1: could create the super super duper smartphones that we all want.
Speaker 1: Super smartphones are already on the horizon. Okay, well secret
Speaker 1: identities too, So so RAM is pretty ubiquitous. I mean,
Speaker 1: it's in just about anything that that computes UM. And
Speaker 1: you know, the technology has been fairly standard for for
Speaker 1: several years now, um, you know, with minor improvements over
Speaker 1: the past decade or so, but um, you know, with
Speaker 1: with Uh, computer scientists working on improvements, uh, completely different technologies.
Speaker 1: Hopefully they'll be able to improve that because it's it's
Speaker 1: critical to basically any type of computing that you want
Speaker 1: or need to do. Um, So it's uh, it's very basic.
Speaker 1: I'm glad we we looked at it because it's, uh,
Speaker 1: it's vastly important to our our daily world these days.
Speaker 1: It's definitely one of the basic building blocks of of
Speaker 1: the computing age. I mean, you know you talk about
Speaker 1: it's not as it's not as basic as say a transistor, right,
Speaker 1: it's like a level up, so it's kind of on
Speaker 1: the molecule scale as opposed to the atomic scale. Right.
Speaker 1: It relies on transistors, so it's it's a little more
Speaker 1: complex than the basic basic building blocks. But without it,
Speaker 1: computing would not be nearly as useful as it is
Speaker 1: because it would take far more time to process operations.
Speaker 1: And even again, even if you have the fastest CPU,
Speaker 1: if it can't access memory, then all it's going to
Speaker 1: do is just be very quick when it needs to
Speaker 1: to find information on the hard drive, and then it's
Speaker 1: all dependent upon how fast the hard drive can deliver
Speaker 1: the information to the CPU. The memory allows the CPU
Speaker 1: to skip that step and it just makes things much faster. Now,
Speaker 1: another potential memrister thing I should say is that if
Speaker 1: you designed a hard drive out of memristers, you could,
Speaker 1: in theory have your hard drive act as memory. It
Speaker 1: would be it would it could in theory behave in
Speaker 1: a very similar fashion, which means you could potentially just
Speaker 1: incorporate RAM directly as part of what the hard drive does,
Speaker 1: and then you wouldn't need RAM anymore, which also means
Speaker 1: that you can load stuff up at at uh in
Speaker 1: the blink of an eye, and that would be phenomenal. Uh. Again,
Speaker 1: that's a potential uh that we may come to see
Speaker 1: one day. It's not something that you're gonna see on
Speaker 1: the market. I don't know else. I haven't gone to
Speaker 1: ce S yet, so maybe hey, look at m rister machine.
Speaker 1: Can I take it? Yeah? No, that's the tildy key
Speaker 1: work alright then, Yeah, let's wrap this up. Guys. If
Speaker 1: you have any questions about any particular subject you would
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