WEBVTT - TechStuff goes to RAMing speed 0:00:00.280 --> 0:00:02.840 Brought to you by the reinvented two thousand twelve camera. 0:00:03.160 --> 0:00:08.920 It's ready. Are you get in touch with technology? With 0:00:09.000 --> 0:00:17.760 tech Stuff from how stuff dot com. Hello everyone, and 0:00:17.800 --> 0:00:20.040 welcome to tech stuff. My name is Chris Poulette and 0:00:20.040 --> 0:00:22.760 I'm an editor at how stuff works dot com. Sitting 0:00:22.840 --> 0:00:27.760 across from me is senior writer Jonathan. It was a bright, 0:00:27.840 --> 0:00:30.880 cold day in April and the clocks were striking thirteen. 0:00:32.560 --> 0:00:35.600 Take it. You're not doing songs anymore. No more songs, 0:00:35.960 --> 0:00:41.000 not movies. These are the first lines and novels. So 0:00:41.040 --> 0:00:44.239 if you know what novel that came from, let us know. 0:00:44.880 --> 0:00:47.839 That's a novel idea. It is. Uh. There was a 0:00:47.880 --> 0:00:51.120 second quote I almost used that was not a novel quote, 0:00:51.240 --> 0:00:54.760 but I almost use it, which is sixty k ought 0:00:54.760 --> 0:00:59.040 to be enough for anybody? A. Yeah, and that's uh. 0:00:59.080 --> 0:01:02.920 That apparently is not an accurate quotation, but at least 0:01:03.280 --> 0:01:06.320 he says it's not it's it's us. It's a possibly 0:01:06.400 --> 0:01:10.759 apocryphal quote from Mr Billy Gates. I feel like I've 0:01:10.760 --> 0:01:13.200 heard that name. So today we are but I can't remember, 0:01:13.240 --> 0:01:14.920 which is good because today we're going to be talking 0:01:14.920 --> 0:01:19.160 about memory, computer memory specifically. Yeah, and Uh, we had 0:01:19.200 --> 0:01:22.319 a lot of people request over over the length of 0:01:22.319 --> 0:01:24.480 tech stuff. Really the entire time we've been doing this, 0:01:24.520 --> 0:01:25.920 we have a lot of people ask us to do 0:01:26.600 --> 0:01:29.360 a podcast about RAM and to kind of talk about 0:01:29.400 --> 0:01:31.880 what RAM is, why you need it, and what does 0:01:31.920 --> 0:01:34.319 it do and how does it work? Which is funny 0:01:34.360 --> 0:01:36.720 because we kept not doing it because we thought we 0:01:36.720 --> 0:01:39.800 already had it. Turns out not so much. I did 0:01:39.800 --> 0:01:42.640 a search for the word RAM in our archives and 0:01:42.760 --> 0:01:47.760 UH saw a lot of programs, but not RAM. And 0:01:47.920 --> 0:01:50.040 I even search for memory. And the only memory thing 0:01:50.040 --> 0:01:53.080 we've done is we've talked about hard drives, which hard 0:01:53.200 --> 0:01:56.520 The relationship between hard drives and memory is a close one. 0:01:56.560 --> 0:01:59.840 It's an important one. And Uh. In fact, if we 0:02:00.080 --> 0:02:03.120 did not have RAM, if we if we had not 0:02:03.200 --> 0:02:06.360 developed that, and we were relying solely upon the kind 0:02:06.360 --> 0:02:09.080 of memory that you would find in a typical hard drive, 0:02:09.880 --> 0:02:13.639 you know, the traditional hard drive. Uh, computer operations would 0:02:13.680 --> 0:02:17.120 take much longer than what we're accustomed to. Yeah. As 0:02:17.160 --> 0:02:19.080 a matter of fact, I can, I can actually deliver 0:02:19.200 --> 0:02:23.520 a personal commentary on that because my very first machine 0:02:23.600 --> 0:02:26.560 was an Amiga one thousand. Uh. Many people have known 0:02:26.600 --> 0:02:29.560 because I mentioned it several times in the podcast, and 0:02:29.919 --> 0:02:32.000 that first machine that I had didn't have a hard 0:02:32.080 --> 0:02:36.440 drive on it. Um so Commodore's instructions. When you first 0:02:36.440 --> 0:02:39.000 turned the machine on, you would once it it got 0:02:39.040 --> 0:02:41.840 into boot up mode, you would see a copy of 0:02:41.880 --> 0:02:45.880 the Kickstart disc. Kickstart basically loaded the operating system uh 0:02:45.960 --> 0:02:50.080 into RAM, into random access memory, and then once that happened, 0:02:50.080 --> 0:02:52.600 you could launch your workbench, which is the equivalent of 0:02:53.639 --> 0:02:56.280 the desktop in what you would see in Windows Lennox 0:02:56.560 --> 0:03:00.560 or the Mac os today. UM So you know without 0:03:00.600 --> 0:03:03.040 that uh you know, when I got my first hard 0:03:03.120 --> 0:03:05.840 drive computer, which was an Amigia three thousand, UM, it 0:03:05.919 --> 0:03:08.040 had a forty megabyte Yeah, you can laugh at that 0:03:08.120 --> 0:03:12.919 hard drive which would automatically load the Kickstart and get 0:03:12.960 --> 0:03:16.000 everything started up for you. So it worked very much 0:03:16.040 --> 0:03:19.880 like our machines do now. But um you know that 0:03:19.880 --> 0:03:22.160 that was That's one of those things that that the 0:03:22.160 --> 0:03:24.680 hard drive takes care of that you didn't that you 0:03:24.800 --> 0:03:28.040 don't have to do, uh now, is load your operating 0:03:28.080 --> 0:03:30.160 system and all that stuff in there. There's also it's 0:03:30.160 --> 0:03:32.880 also important to note the difference between RAM and ROM. 0:03:32.919 --> 0:03:36.800 I would say read only memory or ROM. UM also 0:03:36.880 --> 0:03:40.080 has a lot of that baked into the chips onto 0:03:40.080 --> 0:03:42.520 your computer. There are some things that are already in 0:03:42.600 --> 0:03:45.640 your computer that are part of the UH UM the 0:03:45.680 --> 0:03:50.680 physical hardware. But and and read only memory UH That 0:03:50.800 --> 0:03:54.760 memory is at access sequentially rather than at random, which 0:03:54.760 --> 0:03:57.240 is how random access memory got its name right. And 0:03:57.320 --> 0:04:01.040 read only memory, as the name implies, you can only 0:04:01.360 --> 0:04:04.760 read from that memory. You can't write to it. So, 0:04:04.760 --> 0:04:08.400 in other words, it's unchanging. It is is static. It 0:04:08.440 --> 0:04:10.880 will always be the way it is, unless you were 0:04:10.920 --> 0:04:14.240 to physically remove the chips and replace them with other 0:04:14.360 --> 0:04:17.960 chips or other circuitry. It's always going to be the 0:04:18.000 --> 0:04:21.159 same way. And there's some devices that only have read 0:04:21.200 --> 0:04:24.160 only memory because that's all they require and it's important 0:04:24.200 --> 0:04:27.720 to have. It's UM. It's a very useful type of memory. 0:04:27.800 --> 0:04:31.320 But when you're working on a project, if you only 0:04:31.360 --> 0:04:34.040 had ROM and not RAM, you would have to burn 0:04:34.080 --> 0:04:36.119 a new ROM every time you wanted to save something 0:04:36.120 --> 0:04:39.040 to this it would be a real pain. So, for example, 0:04:39.240 --> 0:04:42.559 if you were to look at uh the good old 0:04:42.839 --> 0:04:45.560 video game console market, especially if you were looking at 0:04:45.560 --> 0:04:51.520 the old cartridge based consoles, the the games, the cartridges 0:04:51.600 --> 0:04:55.080 you have that you would put plug into your console 0:04:55.600 --> 0:04:59.400 had ROMs on them. That was the game itself was 0:04:59.440 --> 0:05:03.400 a ROM. And that's why if you talk about things 0:05:03.440 --> 0:05:07.320 like the main emulator, and I know that's it's kind 0:05:07.320 --> 0:05:10.240 of like saying a t M machine, but the emulator 0:05:10.279 --> 0:05:14.200 for arcade machines UH that you can run on certain computers. 0:05:14.880 --> 0:05:20.960 The emulator's job is to to mimic the circuitry that 0:05:21.040 --> 0:05:23.720 you would find within an arcade machine to run a 0:05:23.760 --> 0:05:28.680 specific ROM or game. So ROMs are used in devices, 0:05:29.000 --> 0:05:32.559 and in some cases are are the only thing within 0:05:32.600 --> 0:05:35.719 that device. There might be some other memory there to 0:05:35.760 --> 0:05:37.560 do things that keep track of a high score. That's 0:05:37.560 --> 0:05:41.800 a little different, but but in general, um, you know, 0:05:42.120 --> 0:05:44.640 there are certain devices that will only have ROM. RAM, however, 0:05:44.760 --> 0:05:47.279 is very important for the way we use computers today. 0:05:48.200 --> 0:05:51.359 Think of RAM as it's a it's a temporary storage 0:05:52.080 --> 0:05:55.400 facility for a computer, right. So it's where you can 0:05:55.440 --> 0:06:00.680 temporarily store instructions and data so that your computer processor 0:06:01.040 --> 0:06:03.880 doesn't have to go hunting through your hard drive system 0:06:03.920 --> 0:06:08.960 in order to find the relevant information to execute a command. Um. 0:06:09.040 --> 0:06:11.680 The way I like to think about this is if 0:06:11.680 --> 0:06:15.440 you're a student, imagine that you have a textbook filled 0:06:15.440 --> 0:06:18.920 with facts will say physics. It's a physics textbook, all right, 0:06:19.240 --> 0:06:22.120 and you've got a test coming up, and you've created 0:06:22.720 --> 0:06:26.000 a crib sheet for you to study from, and the 0:06:26.040 --> 0:06:29.040 crib sheet has bulleted points on it about the major 0:06:29.120 --> 0:06:31.480 things you're going to be covering in your next physics test. 0:06:32.160 --> 0:06:33.839 That crip sheet is kind of like RAM in the 0:06:33.880 --> 0:06:36.520 sense that you can make little notes, you can erase stuff, 0:06:36.560 --> 0:06:40.800 you can replace things, and it has a good instruction 0:06:40.920 --> 0:06:43.280 set for you to work from. Now, occasionally you might 0:06:43.360 --> 0:06:45.960 come across a problem. Let's say you're working on some 0:06:46.040 --> 0:06:48.400 homework that's going to prepare you for this test, and 0:06:48.440 --> 0:06:50.400 you've got your crib sheet in front of you and 0:06:50.440 --> 0:06:53.440 you're working on your homework question, and you realize that 0:06:53.640 --> 0:06:56.800 the information that you need is not on the crib sheet. 0:06:56.839 --> 0:06:58.719 It's just doesn't go that deep. So you have to 0:06:58.720 --> 0:07:01.280 go to the text book to refer to the right 0:07:01.360 --> 0:07:03.520 section to learn the stuff you need in order to 0:07:03.520 --> 0:07:06.480 answer that question. That's kind of like your computer. Your 0:07:06.480 --> 0:07:09.279 CPU is going to refer back to the memory to 0:07:09.360 --> 0:07:12.360 see if the information it needs is there, and if 0:07:12.400 --> 0:07:16.880 it's if the information goes beyond that little memory, if 0:07:16.920 --> 0:07:19.320 it's something that has to actually access the hard drive, 0:07:19.360 --> 0:07:23.120 it will go to the hard drive, same sort of idea. Yeah, 0:07:23.160 --> 0:07:25.840 and um, I would just like to note that when 0:07:25.840 --> 0:07:29.680 I said that RUM could only be access sequentially, that's wrong. 0:07:29.760 --> 0:07:33.040 I was actually thinking of serial access memory or SAM. 0:07:33.720 --> 0:07:36.520 I apologize for that. Yeah, I haven't had enough coffee 0:07:36.560 --> 0:07:39.760 this morning apparently, But yeah, cereal access memory is uh, 0:07:40.160 --> 0:07:43.880 is another form of memory that's not used nearly as 0:07:43.920 --> 0:07:46.840 often today as it used to be. But back when 0:07:46.920 --> 0:07:50.280 we had tape drives, Um, you know, you used to 0:07:50.320 --> 0:07:52.520 have to go all the way through the tape until 0:07:52.560 --> 0:07:54.440 you got to the part where it had the information 0:07:54.440 --> 0:07:57.480 you needed, letter than accessing it. It's just the same 0:07:57.480 --> 0:08:00.360 as if he's had a cassette tape, right, had an 0:08:00.360 --> 0:08:02.320 old cassette tape with music on it, and you wanted 0:08:02.360 --> 0:08:06.000 to listen to a specific song. You had to fast 0:08:06.040 --> 0:08:08.680 forward or play through the tape until you got to 0:08:08.680 --> 0:08:11.200 the song you wanted, and then you could listen to it. 0:08:11.200 --> 0:08:14.080 You couldn't just jump right to the song. For our 0:08:14.160 --> 0:08:17.120 younger listeners, this might seem like a completely foreign concept, 0:08:17.640 --> 0:08:20.240 but yes, uh, lots of us used to listen to 0:08:20.280 --> 0:08:24.200 cassette tapes and if you were really lucky you had 0:08:24.280 --> 0:08:27.400 like the eight track tapes where your options were even 0:08:27.440 --> 0:08:30.840 more limited in order to navigate to the next song. Yes, 0:08:30.880 --> 0:08:33.959 but ROM doesn't necessarily work that way, so I apologize 0:08:34.000 --> 0:08:37.000 for that. But random access memory there, there's certain there 0:08:37.000 --> 0:08:39.160 are different kinds of it. One of the most common 0:08:39.240 --> 0:08:44.120 is dynamic RAM. Yeah, that's that's probably the most versions 0:08:44.280 --> 0:08:49.760 of that are probably the most common used in computers today. Yeah, 0:08:49.800 --> 0:08:52.720 and uh. And the way that random access memory, dynamic 0:08:52.840 --> 0:08:55.880 random access memory is is arranged is that you can 0:08:55.920 --> 0:09:01.600 imagine a grid, right, and the the columns there are 0:09:01.600 --> 0:09:04.800 columns in their rows, and where these intersect, you have 0:09:05.720 --> 0:09:10.280 memory cells. Now, a memory cell, the most basic memory 0:09:10.320 --> 0:09:14.760 cell is essentially a transistor and a capacitor, and the 0:09:14.800 --> 0:09:17.760 capacitor can hold a charge. If the capacitor is holding 0:09:17.760 --> 0:09:20.360 a charge, the memory cell is registering as a one. 0:09:20.760 --> 0:09:23.359 If the capacitor is not holding a charge, it's registering 0:09:23.400 --> 0:09:27.560 as a zero. The transistor access a switch that allows 0:09:28.080 --> 0:09:31.680 the various things. It allows the computer to be able 0:09:31.679 --> 0:09:35.320 to read those particular cells and also to recharge those cells. 0:09:35.320 --> 0:09:39.040 Because here's the thing about capacitors, they do drain. Yeah, 0:09:39.080 --> 0:09:42.240 they can hold a charge. There they're sort of like 0:09:42.320 --> 0:09:46.120 a battery, though they are not identical, so don't assume 0:09:46.160 --> 0:09:49.600 that that's the same thing, but they're they fulfill similar functions. 0:09:49.640 --> 0:09:53.199 Capacitors usually release their energy in a burst as opposed 0:09:53.200 --> 0:09:57.839 to over a prolonged time. But yeah, the capacitors. The 0:09:58.000 --> 0:10:00.040 the energy drains from the capacitors, so they have to 0:10:00.080 --> 0:10:05.600 be recharged regularly and rapidly in order for them to 0:10:05.640 --> 0:10:09.440 maintain that charge and hold onto what we call a state. Yes, 0:10:09.679 --> 0:10:11.880 the state of that memory cell. So the state is 0:10:11.920 --> 0:10:13.760 either a one or a zero. If it's a one, 0:10:14.200 --> 0:10:17.560 the computer has to continually send energy to that uh 0:10:17.720 --> 0:10:20.640 sell in order for it to maintain a one until 0:10:20.679 --> 0:10:22.760 the memory needs to be written over, in which case 0:10:22.760 --> 0:10:24.640 it might be a one again or it might be 0:10:24.679 --> 0:10:26.960 a zero. It all depends on what the information is. 0:10:27.640 --> 0:10:30.000 And you've got the like I said, you've got columns 0:10:30.000 --> 0:10:34.320 and you've got rows, and uh the way the computer works, 0:10:34.400 --> 0:10:37.280 it has all these different little um components to it 0:10:37.360 --> 0:10:42.559 that will detect what the current state is of all 0:10:42.600 --> 0:10:45.200 those different memory cells in order to be able to 0:10:45.720 --> 0:10:48.240 uh to to pull the right information. And in fact, 0:10:48.280 --> 0:10:51.480 the computer keeps a record of which memory sell it 0:10:51.520 --> 0:10:53.320 needs to go to because you can think of the 0:10:53.360 --> 0:10:56.920 intersection of that column in that row as an address. Yeah, 0:10:56.920 --> 0:11:00.400 if you think about it as a piece of graph paper, Yeah, 0:11:00.600 --> 0:11:04.160 kind of the computer just basically keeps track of, uh, 0:11:04.240 --> 0:11:07.559 you know, where each item is in that memory. Yeah. 0:11:07.600 --> 0:11:11.000 If you think of the columns is like things like A, B, C, D, E, F. No, 0:11:11.320 --> 0:11:13.080 sort of like think of it kind of like a 0:11:13.120 --> 0:11:15.719 game of battleship. That's exactly what I was thinking. Yeah, 0:11:15.720 --> 0:11:17.600 you got that. You've got the columns that are maybe 0:11:17.640 --> 0:11:20.920 A through Z, and then you have one through twenty 0:11:21.000 --> 0:11:23.439 six as the rose, and you want to look at 0:11:23.920 --> 0:11:26.840 A four. Well, then you know exactly where to go 0:11:27.480 --> 0:11:29.640 to to pull up that information. You don't have to 0:11:29.679 --> 0:11:32.160 you don't have to go through the entire sequence of 0:11:32.320 --> 0:11:34.920 memory cells in order to get at that information. That's 0:11:35.080 --> 0:11:37.640 a very simplistic way of saying what is happening with 0:11:37.679 --> 0:11:42.440 this dynamic random access memory. One of the disadvantages here, though, 0:11:42.559 --> 0:11:47.319 is that having to refresh that memory constantly means that 0:11:47.440 --> 0:11:53.480 you're essentially slowing down the memory um, which is you know, 0:11:54.320 --> 0:11:56.600 a problem. It's it's something that that requires a lot 0:11:56.600 --> 0:12:00.400 of energy. It requires, uh that you're constant, constantly refreshing 0:12:00.400 --> 0:12:03.720 it and slows down your memory. Now, UM, having more 0:12:03.760 --> 0:12:07.200 memory in your computer is a good thing. UM. You 0:12:07.200 --> 0:12:09.440 know remember when we talked about thirty two bit and 0:12:09.520 --> 0:12:13.840 sixty four bit systems. Um. You know, your your operating 0:12:13.840 --> 0:12:17.000 system and your computer, depending on how they work together, 0:12:17.120 --> 0:12:23.079 can address a certain amount of computer memory. UM. And 0:12:23.280 --> 0:12:26.319 uh you know with if you have if you are 0:12:26.360 --> 0:12:30.640 not taking advantage of the maximum capacity of memory or 0:12:30.679 --> 0:12:34.400 at least you know, as much as your computer can hold. UM, 0:12:34.520 --> 0:12:38.240 not only is it having to uh fit whatever programs 0:12:38.240 --> 0:12:41.040 you're trying to run on top of the operating system 0:12:41.080 --> 0:12:44.720 in that amount of memory, it's also dealing with uh 0:12:44.800 --> 0:12:47.120 constantly having to refresh that memory. So it can really 0:12:47.120 --> 0:12:51.160 slow your computer down. Going back to the grid really quickly. 0:12:51.800 --> 0:12:56.280 The the columns along this grid are called bit lines, 0:12:57.040 --> 0:13:00.360 the rows are called word lines, and then a the 0:13:00.400 --> 0:13:04.760 intersection is the memory cell address. So uh, the what 0:13:05.000 --> 0:13:07.520 when you are wanting when you want to write information 0:13:07.600 --> 0:13:10.000 or when your computer needs to write information to your 0:13:10.120 --> 0:13:12.040 RAM in order for the CPU to be able to 0:13:12.040 --> 0:13:16.400 have access to it to make things run smoothly. First 0:13:17.160 --> 0:13:22.240 it starts sending electricity through the column area, so through 0:13:22.280 --> 0:13:28.640 the bitline um individual bitline, and then the computer sends 0:13:29.360 --> 0:13:34.600 electricity through the appropriate wordlines the right rose. So let's 0:13:34.600 --> 0:13:37.359 say that you you know that you're you're you're activating 0:13:37.440 --> 0:13:41.319 column D that's the one that's being um that electricity 0:13:41.360 --> 0:13:46.160 is running through right now. And you know that Rose five, twelve, 0:13:46.880 --> 0:13:50.319 and twenty three need to have need to be activated 0:13:50.360 --> 0:13:54.240 because those memories, the memory cells at those addresses at 0:13:54.280 --> 0:13:58.040 the intersection of column d uh need to be active 0:13:58.080 --> 0:14:00.800 in order for the information to be there. The computer 0:14:00.840 --> 0:14:05.280 sends this information, the transistor allows the capacity turns to 0:14:05.480 --> 0:14:09.920 take on that that charge, and then there's a little 0:14:10.440 --> 0:14:15.960 um sensor actually since amplifier as well, that receives the 0:14:16.000 --> 0:14:20.680 signal that says this capacitor has has a state of one, 0:14:21.240 --> 0:14:23.560 and that's what allows the computer no, you know if 0:14:23.600 --> 0:14:25.920 it's a one or zero, and collectively all those ones 0:14:25.960 --> 0:14:29.560 and zeros give it the information it needs. Now, all 0:14:29.640 --> 0:14:32.640 of this happens in a manner of a few nanoseconds, 0:14:33.160 --> 0:14:36.640 So don't think like this is taking ages. It's it's 0:14:36.760 --> 0:14:40.400 it's billions of a second for this stuff. When I'd 0:14:40.400 --> 0:14:43.600 say slow, I would put that in quote it right slow, 0:14:43.760 --> 0:14:47.200 like the way we feel when we put something in 0:14:47.240 --> 0:14:49.920 the microwave for a minute and we're thinking, why isn't 0:14:49.960 --> 0:14:54.880 it done yet? That kind of slow. Yes, it's not slow, 0:14:54.920 --> 0:14:56.880 as in, you put something in the oven and four 0:14:56.960 --> 0:15:02.440 days later you've got turkey. Uh the I put an 0:15:02.440 --> 0:15:04.920 old boot in there. There's a turkey. That's the way 0:15:04.960 --> 0:15:08.600 it worked, isn't it. No? Oh, I need to go 0:15:08.680 --> 0:15:11.840 home after this podcast. But at least I'll have some 0:15:11.880 --> 0:15:15.840 warm boots. Uh. Yeah. So this this is all taking 0:15:15.960 --> 0:15:19.800 just nanoseconds for each individual transaction, melal seconds for the 0:15:19.800 --> 0:15:24.320 whole thing. So, but it's happening repeatedly until that memory 0:15:24.360 --> 0:15:26.520 is getting rewritten. And it's happening. You know, it's changing 0:15:26.640 --> 0:15:30.840 rapidly because that's the nature of memory. If you're running 0:15:30.840 --> 0:15:33.760 a lot of different applications and uh, your memory might 0:15:33.840 --> 0:15:37.760 be filling up pretty quickly with all this information. That's 0:15:37.760 --> 0:15:40.800 why the more applications you run, if you're if you're 0:15:40.880 --> 0:15:43.600 using an older machine and you're running a lot of 0:15:43.640 --> 0:15:47.240 different applications, you might feel like you're everything's kind of sluggish. 0:15:47.760 --> 0:15:50.360 And that's why people will tell you like, oh, well, 0:15:50.360 --> 0:15:53.080 you need to close some of these applications because it's 0:15:53.120 --> 0:15:55.200 taking up space. In the memory, and the CPU is 0:15:55.240 --> 0:15:58.160 having to work harder to get the information it needs 0:15:58.520 --> 0:16:03.000 to act to execute your hands. So, uh, you know 0:16:03.120 --> 0:16:06.040 that that's how that all plays in. That's why people say, oh, 0:16:06.160 --> 0:16:07.640 if you want a computer to go faster, you need 0:16:07.720 --> 0:16:10.360 more memory, because then you can you can actually run 0:16:10.440 --> 0:16:13.280 more applications. That tends to be a very common problem 0:16:13.440 --> 0:16:16.080 that people run into, right that they're like, my computer 0:16:16.160 --> 0:16:18.200 is so slow, and you look at and you're like, well, 0:16:18.240 --> 0:16:21.200 you've got fifteen applications open, and three of them are 0:16:21.200 --> 0:16:24.760 pretty heavy duty, um, you know, or graphics intensive or whatever, 0:16:24.960 --> 0:16:28.600 something that's going to require a lot of processing. That 0:16:28.640 --> 0:16:31.880 would be why it's both processor speed and the amount 0:16:31.920 --> 0:16:34.280 of memory you have. The two are very much important. 0:16:34.560 --> 0:16:38.160 And also when we talk about Moore's law, More's law 0:16:38.200 --> 0:16:43.080 plays into the into memory as well, because dynamic random 0:16:43.080 --> 0:16:45.840 access memory, the nice thing about it is that, well 0:16:45.840 --> 0:16:49.200 two nice things about is that it's relatively inexpensive and 0:16:49.360 --> 0:16:52.440 it doesn't take up a lot of physical space when 0:16:52.440 --> 0:16:56.280 you're designing memory chips. There are other types of random 0:16:56.280 --> 0:16:59.880 access memory, not just dynamic. Their static random access memory. 0:17:00.480 --> 0:17:04.880 And static random access memory uses uh something a logic 0:17:05.400 --> 0:17:08.960 construction called a flip flop, Yes, not a sandal. I 0:17:09.080 --> 0:17:12.439 was gonna say, you're gonna and it comes out as 0:17:12.520 --> 0:17:17.320 chicken already know that doesn't work well. The static random 0:17:17.359 --> 0:17:21.480 access memory, um, yeah, I mean it one of the 0:17:21.520 --> 0:17:24.800 benefits of eas now flip flops. Actually we uh, you 0:17:24.960 --> 0:17:30.240 go back to the Boolean logic um reference. But basically 0:17:30.240 --> 0:17:35.760 a static RAM has the benefit of being a lot 0:17:35.840 --> 0:17:39.600 faster than dynamic RAM. Well, for one thing, what it does, 0:17:39.840 --> 0:17:42.399 once it has a state, it will hold that state 0:17:42.520 --> 0:17:44.520 until you tell it to change, So it doesn't In 0:17:44.520 --> 0:17:47.879 other words, it doesn't it doesn't require to be recharged, 0:17:48.000 --> 0:17:52.080 doesn't have a capacitor that is leaking energy and has 0:17:52.119 --> 0:17:55.800 to be refilled. So once you once you set a 0:17:55.800 --> 0:17:57.880 flip flop to one, it's gonna stay a one till 0:17:57.920 --> 0:18:01.080 you tell it to be a zero. So that sounds great. 0:18:01.119 --> 0:18:04.160 Why don't we use static RAM instead of dynamic RAM 0:18:04.240 --> 0:18:07.600 for our you know, main RAM and our computers. Two reasons. One, 0:18:07.720 --> 0:18:11.200 it takes up more space, so you end up having 0:18:11.359 --> 0:18:14.240 problems like especially with things like mobile devices or or 0:18:14.400 --> 0:18:17.880 laptop computers. You start running into the problem of while 0:18:17.920 --> 0:18:20.000 you can only fit so much into a form factor 0:18:20.040 --> 0:18:23.160 before he gets clunky, right, right, You need more transistors 0:18:23.200 --> 0:18:25.840 for static RAM. Yeah, yeah, four to six for each 0:18:25.840 --> 0:18:29.199 flip flop. So that's and each flip flop is is 0:18:29.240 --> 0:18:34.720 representing one memory cell. So and granted, these transistors that 0:18:34.760 --> 0:18:38.040 we're talking about are on the nano scale at this point, 0:18:38.119 --> 0:18:40.760 you know, we're talking about tiny, tiny, tiny transistors. But 0:18:40.800 --> 0:18:43.159 even so those add up if you need to have 0:18:43.240 --> 0:18:46.440 the amount of memory that you're accustomed to. So they 0:18:46.480 --> 0:18:48.760 are they take up more space, and they're more much 0:18:48.800 --> 0:18:52.480 more expensive. So static RAM is not something you're gonna 0:18:52.520 --> 0:18:56.679 find in every single kind of device, although as you know, 0:18:56.720 --> 0:18:59.399 as the technology has improved, those prices do tend to 0:18:59.440 --> 0:19:01.959 go down, so we do see more and more of that, 0:19:02.040 --> 0:19:04.320 but dynamic RAM is still probably i would say, the 0:19:04.359 --> 0:19:10.280 most popular by far. Um. There there's another potential change 0:19:10.359 --> 0:19:15.359 coming up, a new development that could really uh impact this, 0:19:15.440 --> 0:19:17.880 which we can get into in a little bit. Okay, Yeah, 0:19:17.920 --> 0:19:20.240 I was gonna mention too though, that that static RAM 0:19:20.320 --> 0:19:24.200 can be found in your computer, probably because um, if 0:19:24.240 --> 0:19:28.240 you've seen a list of computer specifications, perhaps when you're 0:19:28.240 --> 0:19:31.000 shopping for a new machine and you see the cash 0:19:31.359 --> 0:19:37.280 referred to, um, your computer's cash is uh, probably static RAM. Yeah, 0:19:37.320 --> 0:19:41.480 a lot of CPUs have this built in. Uh, A 0:19:41.480 --> 0:19:44.240 lot of the ones that use multi threading, that have 0:19:45.160 --> 0:19:48.560 multi core processors. A lot of these CPUs have their 0:19:48.600 --> 0:19:52.600 own sections of memory built And it's not it's not 0:19:52.640 --> 0:19:55.320 your computer's RAM, it's something that's specifically part of the 0:19:55.359 --> 0:20:00.400 CPU chip set that is there to help make make 0:20:00.480 --> 0:20:04.400 those those data transfers even faster, so that it makes 0:20:04.440 --> 0:20:10.840 it very efficient. And for the the most commonly used commands, uh, 0:20:10.960 --> 0:20:15.720 those would be stored within the cash. So in that 0:20:15.800 --> 0:20:19.040 crib sheet example I gave, let's say that you even 0:20:19.080 --> 0:20:21.359 had a little note card next year, a crib sheet 0:20:21.440 --> 0:20:24.760 that had the four formulas you're going to use them 0:20:24.800 --> 0:20:28.720 most frequently in that physics test, and so you've got 0:20:28.760 --> 0:20:31.760 those there because this way, no matter what you know, 0:20:31.800 --> 0:20:33.760 you just have to glance at the at the note 0:20:33.760 --> 0:20:35.960 card and like, that's that's the formula I need. And 0:20:36.000 --> 0:20:38.359 you plug it in and you make it, you make 0:20:38.400 --> 0:20:41.840 it work and whatever. The problem is. Your CPU is 0:20:42.000 --> 0:20:47.040 really really good at executing operations upon data, but it's 0:20:47.119 --> 0:20:49.119 stupid in the sense that as soon as it's as 0:20:49.119 --> 0:20:52.320 soon as it's finished doing that, it's forgotten. There's no, yeah, 0:20:52.359 --> 0:20:55.040 it has no memory of its own other than this 0:20:55.040 --> 0:20:58.560 this cash that we're talking about. A CPU on its 0:20:58.400 --> 0:21:02.800 the very basic CPU has no memory, so it can 0:21:02.920 --> 0:21:05.200 do stuff, but as soon as the task is done, 0:21:05.359 --> 0:21:09.160 it's like a blank slate all over again. That's that's 0:21:09.160 --> 0:21:12.600 why we have to have memory in order to get 0:21:12.600 --> 0:21:15.600 this to work. If if the CPU could somehow remember 0:21:16.200 --> 0:21:19.280 on its own, then you'd have other issues like, well, 0:21:19.320 --> 0:21:21.800 now you needed to do something new, So how do 0:21:21.840 --> 0:21:24.840 you write over what you had before? Do you just 0:21:24.960 --> 0:21:26.840 add to it? If you add to it, how long 0:21:26.880 --> 0:21:29.040 until you reach capacity? And you can't do anything with 0:21:29.040 --> 0:21:31.320 that CPU other than the stuff that you've already done. 0:21:31.960 --> 0:21:34.480 So you know, this is why the whole idea of 0:21:34.480 --> 0:21:37.719 the random actis memory that could be rewritten very quickly 0:21:38.080 --> 0:21:42.280 was so important, because otherwise you limit the functions that 0:21:42.400 --> 0:21:44.840 your computer is capable of doing. You know, there was 0:21:45.200 --> 0:21:48.000 this computer is great at adding and subtracting and dividing, 0:21:48.119 --> 0:21:51.359 and after that you can't do anything else because that's 0:21:52.240 --> 0:21:56.919 I was about to install Pacman, but darn it, I 0:21:57.000 --> 0:22:00.560 already took up all of its space with these three functions. Well, yeah, 0:22:00.600 --> 0:22:03.280 so you've got uh and and we're we're sort of 0:22:04.080 --> 0:22:06.680 filling out the whole computer. So you've got your your CPU, 0:22:06.840 --> 0:22:09.240 and you've got a CASH to help it remember stuff 0:22:09.240 --> 0:22:12.840 that it needs to do basic operations. And then you've 0:22:12.840 --> 0:22:15.680 got your your memory, your RAM, your dynamic RAM that 0:22:15.840 --> 0:22:18.919 that's over here managing the stuff that you've got going on, 0:22:19.040 --> 0:22:24.320 your your word pressing, your word uh processor uh stuff, 0:22:24.359 --> 0:22:27.280 and your your graphics program, the stuff that you have 0:22:28.200 --> 0:22:31.840 your browser, your your email program. But you also have 0:22:32.240 --> 0:22:35.720 uh in your modern computer, you've got your graphics processor 0:22:35.880 --> 0:22:39.080 chip and in a lot of cases, UM, and I'm 0:22:39.160 --> 0:22:41.240 I'm just hedging my bets here that somebody has some 0:22:41.280 --> 0:22:44.560 weird computer that doesn't have this also has its own 0:22:44.680 --> 0:22:49.879 RAM UM to help it pro specifically process graphics. UM. 0:22:50.040 --> 0:22:52.760 So that RAM in general is off limits to the 0:22:52.760 --> 0:22:56.000 rest of the machine because it's saying no, no, no no. 0:22:56.200 --> 0:23:00.280 This memory is specifically to help us render graphic on 0:23:00.320 --> 0:23:04.399