TechStuff Looks at Video Cards

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Sitting across from me, as is senior writer Jonathan he there, and I want to warn you all today's episode maybe graphic that's correct, it's about graphics cards. We have received lots of questions and requests for us to do an episode about graphics cards, some of which hounded us through multiple forms of media. And so today you get your wish, we're gonna talk about graphics cards. These are the things

that got me into console gaming, which is true. No, So, Chris, you and I remember, I mean we were we were both using computers during the nineties when there was the kind of revolution in personal computers where and a a an independent secondary graphics card became a necessity if you wanted to stay up to date with the latest games

that were coming out. Yeah. I remember with my very first Amiga how they would talk about there were their secondary chips on the motherboard that we handle additional operations, not just the one processor. And I think, um, it probably seems silly to a lot of us now, like, oh, well,

of course you know that would be important. But you know, as computing has gone on, we've realized some that although you have you know, Moore's law, which basically just you know, talks about computing power growing exponentially, and you say, well, okay, you know you've got more and more powerful computers, but we've realized over that time too that although you may have more powerful processors, Dividing tasks up between multiple processors

is a better way to compute because you can accomplish more when you divide these jobs, and uh, you know, it's it's more efficient that way. It's it's very simple. Yeah, So a graphics card job essentially is to really manipulate computer memory at a very rapid rate so that information coming in can be converted into graphic information that's going to be displayed upon a monitor of some sort. And it's almost its own computer. Yeah, it's it's it's its

own processor, certainly. And the idea is that this takes some of that burden from the CPU and it shoulders it itself so that the CPU can um sort of become like a manager. The CPU sends the instructions to the GPU, which then takes care of calculations and and it's it's designed to do that in a very streamlined,

fast way. And part of that design is this idea of parallelism, which is what Chris was talking about, where you have your your chip created in such a way to process sets of instructions in parallel with each other because those different sets of instructions don't depend directly on each other. You know, if you think about computer problem. One type of computer problem could be an ongoing uh calculation where the outcome of the previous calculation determines what

the next calculation will be. Right, So we'll just say that for the first calculation, we're gonna do something really simple. Just for example, say that the first calculation is two plus two and the the output is four, and then the four from that first calculation is used in the

second calculation. Where you have another variable, Well, we'll say that for the purposes of this problem, that variable is going to be eight, and whatever the product the whatever the sum is from that first calculation gets added to eight. So the the second calculation depends upon the outcome of the first one. The two plus two is four. Well, now I've got the the sum of that first calculation four. I can now add that to eight to get twelve,

and so on and so forth. Well, with all those calculations depending upon one another, having a single processor makes sense. You can't really divide that up because you don't know what the outcome is going to be of a previous calculation,

so you can't move forward until you get that. But there are other computer problems which we have talked about several times on this podcast that you can divide up because they are not interdependent that way, and have a processor or several processors work on that problem, on those problems, and the outcome ends up creating whatever it is you need and UM. In that case, the GPU design was meant to do that. So we had parallel processors with

GPUs well before you started seeing multi cores in consumer computers. Yeah, yeah, that's true. By the way, if you run across computers that offer perpendicular processing, I don't recommend it they I wasted a lot of money once anyway, being so obtuse UM. Actually, when you look at the parts of a graphics card, UM again, they seem rather you know common sense. You've got a graphics card is its own motherboard, It has

a its own processor on it, UM, and its own memory. UM. You may actually see, you know, specifications, I remember seeing specifications for how much v RAM, video RAM or or graphics memory. UM. That's all part of what you see on the graphics card. And some graphics cards are you know, customizable. You can you can add memory. UM depends on your computer course, and and all of that also depends on your your the type of graphics card you use depends

heavily upon the kind of motherboard your computer has. That's true. That's true. Not all motherboards can support all graphics cards. It depends on especially if you have an older computer. There comes a point with older computers where the newest

video cards just the old motherboards can't support them. So that's one thing to keep in mind that the motherboard your your computer's motherboard has a you know, a shelf life really and at some point it does become obsolete, at least in comparison to the latest hardware that comes or the latest components that are out on the market.

And basically, uh, well, I can't think of a computer that doesn't have a video output of some kind on it, even even laptops or ultra books, you know, things that that are designed to have fewer ports than things because it's streamlined. Even those machines generally have UM some kind of video output. Of course, the main one on those would be at their own screen, but um coming off

of the graphics card. You need to uh to be able to display the results, so you know, they'll they'll generally have some kind of connector UM and of course, key to this all is your operating system, because your operating system is uh, what is doing basically the traffic management. So let's say, uh, probably the main reason we talk about graphics cards these days are for you know, really three things games, um, high resolution video editing or or

you know, graphics photo editing. You know, those are the reasons we really talk about the graphics card. I mean, if you say, yeah, I've got to surf the web on my computer, you don't go, yeah, but what kind of graphics card you got, man? I will add I will add a fourth a fourth yeah, which has nothing to do with graphics. Okay, it's what people have started to use GPUs to do. I figured we'd talked about

that way, which goes back to the parallel processing. So the fourth one, I would say, is parallel processing that does not necessarily go back to video processing. So and that can be for lots of different stuff. I know

specifically which one you're thinking about. But because we did our our episode on on password security and talked about how GPUs have been used to help crack passwords through brute force attacks, but they can also be is to do other parallel processing, not just you know, cryptography, No, that that's true because UM, well, actually uh we had talked about it on our our podcast about about the

mac os ten snow Leopard. One of the changes was that they added the ability to uh um send instructions.

And that's really what I was sort of getting at with the the operating system is, you know, it's let's say you're playing a game and uh you know, you have the game itself, the instructions that are going out about where your character is and where it's moving across the screen, and it's sending other instructions about how to render that on the screen to the graphics processor card, which takes care of computation for things like the number of polygons that you see on the screen, how fast

those that information can be displayed. So they work in concert through the help of the operating system to uh manage the rest of the stuff and the graphics specific stuff with the two different the two different cars, and mac Os ten is able in the newer incarnations of the operating system is able to uh um, and I assume that's true for newer versions of Windows and Lenox as well as you know, able to send instructions to

the graphics cards. So Let's say you are surfing the web and maybe you have a music playing on you know, music player service, and you've got email going on, and uh, you know, five or ten other little things going on in the background, your calendar software. UM, your graphics card may not be working over time. So the processing uh, you know, the the operating system goes, hey, since you're not busy and you handle some of these other instructions,

kind of take a load off this couch. Yeah, exactly. So it goes in and helps move the couch, um, so to speak, and take some of the load off the main processor, which which is ingenious that any operating system would be able to do that. Um, And it

just so happens. I know about that one because we were talking about it in that But you know, the operating systems have become so much more sophisticated and to be able to take advantage of that specifically, UM, to take a load off of the main processors is excellent. The things that determine how fast a graphics card is, uh, it's more than just the GPU clock speed of the processors. So keep in mind the heart of this graphics card is a processor. We call the GPU. The graphics processing unit.

And and it's it's very similar to a CPU. I mean that it's job is to crunch data. It's just in this case most of the time that data has to do with rendering graphics. UM, so the clock speed is definitely important. And clock speed, of course, that's generally speaking, the number of instructions a CPU can carry out within

a second. Uh, that's the number of cycles. Because keeping in mind that when I say instruction, really instruct it's really cycles, and some instructions require multiple cycles to complete. I want to make sure I get that before people are like, well, you know actually, and people are going to mention the fact that processors can be overclocked or underclocked. Yeah, that that speed is a rating that the manufacturer gives it that basically says, this will operate the way we've

set it up on this board. It will operate at this speed it's gonna and it's a safe speed. It's not going to cause the processor, processor to overheat falls. It falls within certain operating parameters that are considered to be optimal for that system. So yeah, it's the rated speed. Yeah, and just like CPUs, you can overclock GPUs aboutely want to. In fact, there are a lot of video gamers out there,

that's what they do. Uh. So that's one thing that determines how fast a video graphics card is able to handle graphics. But that's not the only thing, because you also have to worry about getting information to and from that uh that that processor. So the size of the memory bus is really important. The memory bus this is kind of you can think of that is sort of like the highway between the memory and the processor. And you want a nice wide highway so that you can

shove as much data towards that processor as possible. Because the processor, if it's really fast and is able to handle a lot of instructions, that doesn't matter so much. If it can't get the data it needs fast enough, it may just be that, yeah, I'm super smart, but you're giving me math problems at a rate that is, you know, nowhere near my capacity, and so a lot of this power is going to waste. So the memory bus is a very important part of that equation, you know,

because you you you said the memory buses. It's like well, and and that's the funny part about that is if you're thinking about it in terms if that if you made that visual connection to it's not um it really is. The bus is the connection itself, not because I was actually thinking of bus and what in the term given in my in the right context, not in the vehicular

one I want. But also other things that that determine the speed include the amount of available memory, so that onboard memory that's on that graphics card plays a big part. That's just that's just as true in your computer for general computing purposes. You know, your computer needs a good amount of memory, so the CPU does not have to constantly look for the information within your systems hard drive.

That slows things down. So keeping more and more data in memory means the CPU doesn't have to consult the hard drive so much and things just move at a faster clip. Very important when you're rendering graphics, because you know, you want to be able to render graphics at a really good speed. Humans like in general twenty five frames per second. That's a good speed for us. It's hard for us to detect uh problems at anything that's faster than that. But for high you know, really action oriented

video games with lots of high speed stuff. Stick Steve frames per second is generally considered, that's your goal. You want to hit sixty frames per second because you're not going to have too much blurring or artifacts or other problems if you're able to display information at that speed and uh and so that's really important as well. The memory clock rate is also important. Memory bandwidth um and uh. If you're using an ancient system, ramdack speed. So ramdack

that's uh. When when the process is handling this information, it's all digital, right, it's all ones and zeros. Some of us who have older computer systems may have display that's not digital. We might have an analog display, which means you have to convert those signals from digital to analog. That's what the ram dex job is. But these days most displays are digital. If you were to go out and buy a system now, it would be it would have a digital display. Analog just doesn't really that's not

a thing anymore. So it's really for people who have older systems they would have to worry about the ram dag issue. In fact, I'm sure that it's being phased out of almost everything at this point because I mean, you know, why would you be using this older monitor when you could go out and get a new display. Tune in this week is Captain Atomic takes on the evil of ram Dak. Yeah, yeah, different different Ramdackum you

will phase him out. So and like you were saying that, the job of this is to to to the the job that we were intending graphics cards to do, I should say, was to render graphics. And uh so like the polygon issue, that's generally speaking, it tends to be triangles a second, and uh and and these these little bit tiny triangles are what make up the various surfaces you see in represented in computer graphics. Yeah, we're talking primarily three dimensional type stuff, three D graphics, so that

there's at least an illusion of depth. In fact, that's really where the graphics cards came out of. You know. Um, before that, you might have a GPU in a computer, but it would be uh incorporated directly onto the motherboard. It wasn't an additional card like you said. The Amiga had them. The Amiga is one of the earliest systems to have its own GPU. Before that, you could have graphics that were vector based graphics, like you know, the

the video game Asteroids was vector based graphics. Yeah, these are games vector vector versus raster we're talking about here, Yes, I love those. We can stop giving examples, but I guess it helps to explain what the differences between vector graphics and raster graphics. Vector graphics graphics are mathematical there, they're like line art exactly. It's it's geometrical shapes that are based on mathematic uh, calculations. So these are lines

and curves points. They could be shapes like polygons and uh. The nice thing about vector graphics is they are really scalable. You can it's dependent upon what your machine can do, not dependent upon the file. Uh. So in other words, you can a vector graphic at a certain size is going to look just as good or not as good as it will be at a size many many manion times larger than that. It all depends on the equipment,

not on the graphics file. Yeah. Now, now, raster graphic or bitmapped graphics UM is made up of basically made up of little dots and um. That's the way are are our printers work, That's the way our displays works. So this is raster graphics that's much more common. Yeah. So well, if you talk about a good example, I

think for what you were mentioning was photos. Yeah, if you've ever taking a photo, put on your computer and decided you wanted to blow it up, you may notice that it starts to look rather grainy, block and yeah or blocky. You can see a little sharp angles where the which or the outlines of the pixels really yeah, and and then and what it's doing is the computer is basically having to make up information in between the

little dots of information that came with the picture. So you know, it's it's going, well, that's kind of green and this kind of orange. All I'll split the difference and uh and uh, you know, when you make something smaller,

it's easy because you're compressing the information. It can go, oh well, I don't need these pixels, so I'll toss them out and uh, you know things that you can only shrink a photo without distorting it, but expanding it as a different question and a graphics vector graphics aren't like that because when you blow something up, it goes, oh well, basically it's this point in that point, I'm you do the math. It looks fine. So the games

and stuff that we play, those are raster graphics. That's where we've got those those images that are made up of pixels. So, um, you know, that's trying to create a uh, a detailed graphic representation of a character, especially character that's in motion and doing lots of stuff at a at a good frame rate. That's that's a pretty

intensive process as far as processing power is concerned. Um. And that's why we had companies start to develop graphics cards to help take this load off the onboard graphics chips that computers had because they just weren't up to

the task of processing that amount of information. Which meant that if you went out and you had a regular PC, will off the shelf PC, no additional graphics card other than what the onboard graphics card was, uh, and you come home, plug it in and you load up that first person shooter game that's brand new, it would not

run very well. You would have to run it at a very low detail quality, so that it's having to do fewer polygons on the screen at a time because it just didn't have the processing power to keep up. Or you'd have to really and or you'd have to really reduce the frame rate so that the actual experience

is not as smooth or pleasant. And you might think, wow, this is a terrible game, but really it's because the hardware you're running on isn't up to the task of running the game at the the experience that the game developers intended. So the graphics cards were what allowed you to plug it in, usually in a well. Back in the day, it was PC I or UM white a g P. Yeah, those were the two card slots to

would plug them into. Today it's PC I Express almost exclusively um where which has got a It's it's a more efficient and faster way of transferring information from a card to the motherboard and uh and out to a display. So you would plug you would plug this in, and it was designed to be pretty easy, I mean relatively speaking.

You're not soldering or anything, opening up a computer case, sliding a card in an expansion slot, screwing it tight so that it's not gonna wiggle in the case, close it back up, plug in your your peripherals, and you're good to go. It's a little more complicated now because if you're getting a state of the art, fastest possible processor you can get for a GP, especially you're getting two of them, because there are a lot of motherboards

out there now that support dual graphics cards. Um, some of these are so powerful that they require more power than what the motherboard can supply. More power. Yeah, so they have to plug into your computer's actual powers apply, not the motherboard. And uh, particularly if they are so powerful that they have their own onboard fans. The fan used to help distribute the hot air so that the

processor does not overheat. Yeah, well that's that's one of the problems that that prevent high end graphics cards from being included with some laptops, which is simply because it's easier to put in a high end graphics card that requires its own fan in a tower case, really a towered desktop computer case, because there's simply more room for it. Um. Less room on a laptop in general, less ability to

find a way to disperse that extra heat. So not only are you're you dealing with the main central processing unit CPU, you're also dealing with the GPU. And you're going, wow, this is going to burn someone's legs off when they put it on their lap because I don't actually have a good way to disperse a seat, or it's going to cause the machine to shut down after twenty minutes of working, which is probably not quite as bad as burning somebody, but it's irritating, irritating, but not disfiguring. So

there's that you take that home. But but yeah, I mean and and uh also easier to uh to get into a desktop machine to swap a card or add a card um, as you were pointing out, some you know support multiple Um. Then it would be necessarily with the laptop, especially something like an ultra book that is put together just so so that it makes that nice slim form factor that those are pretty much you're you're out of luck there. Um. The yeah, it's uh, it's the the graphics cards tend to be more of a

desktop type of component than laptop. And I mean, for for the reasons you you pointed out, um, which is also one of the reasons why uh, serious hardcore video gamers on the PC tend to prefer desktop setups rather than a laptop. Because even if you go out and you buy a state of the art gaming laptop right now for thousands of dollars, and it might it might right now rival the best desktop computers out there. The advantage of the desktop computers have is that, in general,

their machines are much more customizable and easily modified than laptops. There. I'm sure there are exceptions out there, but that's the general rule, and it's a pretty safe one because it's just tends to be a lot easier to fiddle with stuff that's inside a desktop case because you've got a lot more space there than you do with a laptop. There may be cards that a laptop just physically cannot

accommodate because there's just not the room. And if you've seen some of these video cards, it's not hard to imagine because some of them look like they are you know, some of them look like they came straight out of a video game, like this looks like it's a magazine clip for a futuristic machine gun or something. Uh. Some of them am like wow, I don't know that I have a computer pretty enough to install this thing in. And in fact, some of them, I would argue the

design here. They've created aesthetic for the video card, which never used to be a concern. Right. These were cards that just fit inside a computer case. You never saw them unless you had to open the case. But now we've got these cases that have exposed sides. So suddenly the aesthetic design of the graphics card has become a consideration well also, um, people who play a lot of I would argue this is probably the case for uh,

hardcore serious gamers. Two, is it's nice that it looks cool because you're buying this, you know, updated graphics card that's going to be able to do all this extra pixel rendering, and you know you want to look cool. And some of these graphics cards cost as much or more than video game consoles, which brings me back to the whole thing about saying, you know, video cards are

what made me a console gamer. It's not quite as simple as that, but it is very close in the sense that I saw that, you know, because I was there when the video game cards, the standalone graphics cards started to become a thing, um, and I could see that within six months to a year, the cards that had been out on the market were no longer able to run the most current games at their ideal settings.

And that was a pretty rough wake up call to me saying that even if I had saved up the money to buy a video card for my computer and I had swapped it out, and I thought, wow, this is an amazing experience. Six months to a year down the road, I would feel like I'd have to do that all over again just to keep up with the

video games that were coming out at that time. It's a constant cycle, or can be a concert cycle of needing more memory and a new processor and a new graphics processor with more memory, and having to upgrade one or the other or all of the above. Right you you eventually get to a point, like we said, where the motherboard can't support the latest graphics card. Then you're like,

all right, now I gotta get a new, entirely new system. Uh. And so now, if I were the kind of person who I was constantly building computers, that might not be as big a deal because I could replace components as I needed to. And one can argue that maybe through the lifetime of a video game PC you spend less money than you would with a console game, depending upon how much gaming you do, because console games do tend to be more expensive, and they do tend to be

more expensive for longer than PC games. PC games get marked down, generally speaking, faster than console games do, so there there is an argument to be made that you could save money over the long term. If you are an avid gamer, you buy a lot of games. Um, if you go with a PC gaming rig, especially if you decide to build one yourself, as opposed to buying something that was customized off the shelf, like if you

actually go out and get the components. Um. It also gives the developer a little bit of an added advantage too, because if they're developing a title for say the PlayStation three, they know exactly what kind of graphics card is in there, so they can play to its strengths. Yeah. And actually that was a real problem early on too, is that you would get games that would be compatible with certain

graphics cards but not others. And then you know, you might have a state of the art gaming computer back in the mid nineties, and then find out that even though you have a state of art gaming computer, you still can't play certain games because they are not compatible with the the hardware you have. Um. That's when you shake your fist in the air and screen con Yeah. We should also mention that effectively, the video card industry is a duopoli. There are two companies that that's essentially

that's who you go to. Yeah, there's Nvidia and there's a m D Yeah, also known as a t I. Back in the day, but A m D purchased them, acquired a t I. There are there are others until makes some graphics cards, um, you know, and they're they're really others. But yeah, when when we're talking about this, uh, probably the listeners that wanted us to talk about this would already know that those two are the big players

and they they're in a constant game of one upsmanship. Uh. The fastest card I could find so far, at least as far as clock speed goes, not performance. Actually, as far as performance goes, is not the fastest. But with clock speed, uh is uh without over clocking is uh? The A m D Radio on h D seven seven seven zero Giga Hurts edition, which it's one giga Hurts GPU and um it again that's without overclocking. But uh,

that's not that fast. But yeah, when it when all it's doing, when it's handling primarily graphics, having that dedicated processing power behind it, you know that don't sneeze at the one gigga hurt. Now again, through the testing, it did not perform at the same level as some of the top of the line, most expensive cards that are out there. Uh. And part of that is just because you know, the Again, it's it's more than just the

clock speed. We talked about that. So that's that's kind of the roundup on graphics cards in general, Like we had said, they're being used to process information beyond just graphics because it's got this parallel process and capability, so you can use it for things that require lots of parallel computational problems, things that you know, there's a lot of scientific and medical applications for that kind of technology, but the one that we talked about most recently is

cryptography and cracking codes and using parallel processing to run a brute force attack where you're just running lots and lots of variations on various passwords to try and determine what the hashing algorithm is for a for for a password site. So the unless the operating system is specifically assigning it tasks, you would have to have software that

specifically directs information to the graphics card. And um, the people who yeah, there there are programs that specifically tell the GPU to to go to work on these these problems. So um, and then it's not specifically specific enough to where the hardware is. It's like, well, it's not a piece of graphics, so I can't do this. You know, it's very capable of handling that. So alright, So I

think that wraps up this discussion on video cards. I hope that that was That was satisfying to our listeners who were asking us repeatedly to cover it. Actually, you know, I sound like I'm I'm exhausted by it. I'm not. I really I like seeing enthusiasm from our listeners. That's very It's a good thing. So if you are enthusiastically interested in a particular topic and we have not covered it, or perhaps we covered it a long time ago and it's darn near time that we recover it, let us know.

Send us a message. You can send us an email our addresses tech stuff at Discovery dot com, or let us know on Facebook or Twitter. Our handle at both of those is text stuff h sw and Chris and I will talk to you again really soon for more on this and thousands of other topics because it has staff works dot com. See guys, I told you we talked to you again really soon. That really soon is

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