TechStuff Classic: TechStuff Overclocks a CPU

and it's titled Text Stuff over Clocks a CPU. Now, let's go ahead and get this out of the way. CPUs have certainly advanced since two thousand twelve, but the general principles behind overclocking remained the same. So I hope you enjoy this discussion that Chris and I have about what overclocking is and how it is accomplished and take it away old version of me and old version of Chris Paulett. Today, to start off our episode, we have

a little Facebook feedback you be. This comes from Brian who says, I've been listening to you guys since almost the beginning. Keep up the great work. I was wondering if you could do a podcast about overclocking. You can talk about what it is, how it works and the pros and cons of it. I've had some experience myself and can tell you it's well worth it. Can't wait to listen to your next podcast. Well, Brian, this one

goes out to you. And we've talked a little bit about over clocking and past episodes, particularly anything where we talked about CPUs and clock cycles. But but let's let's kind of go back and talk about what a clock cycle is and why it's important and what overclocking actually means. Yes, now, this is something we talked about a long time ago. A long long time ago, we talked about the Mega Hurt Smith and you know, the giga Hurt Smith, about the the speed of the processor and what it means

and how it's really not necessarily all that important. In fact, it's kind of funny looking at computers now, um, because now that the dual core and quad core processors and and let's just say multi core processors, um, some of them look like they're going backward because you'll see, you know, a two gig or hurts processor and you wait a minute, the one I have now is a three point two y a three point two gigg hurts. Well, yeah, because it's got multiple cours processing, it's able to do this.

But the clock speed is is basically the rate at which a processor is handling instructions. Very good. Yes, um, I actually saw a pretty interesting analogy on a Yale website. This was written by H. Gilbert, and Gilbert said that think of it like a high school. Right, So you're in class and then the bell rings, and that signals the end of class. So you leave alrighte and the second bell rings and you have to go to your next class. So those two bells, he says, think of

that as a clock cycle. The first bells a tick and the second bells of talk, and the entire school reacts to those bells. It's not like one class gets a bell and then three minutes later another class gets a bell. It goes across the entire school. So, uh, think of a clock cycle on a on a CPU is the same sort of thing, except in steps, students, we're talking about data ones and zeros, so ones and zeros, and and that at every clock cycle, ones and zeros

are moving around. And essentially every task you want a computer to do requires a certain number of cycles. Uh, some tasks only require one cycle and some will require multiple cycles because the task actually has more steps than what you might first imagine. And this changes over time. I should add back, you know, several years ago, many years ago, a couple of decades now, adding two numbers together might take six or eight clock cycles to complete, uh,

and today it might take one clock cycle. So it's become more efficient. So that's one way that CPUs have sped up over time. But an others that we've actually managed to fit more clock cycles in per second, and that's the speed we talk about with processors. That's how many clock cycles or pulses if you prefer, go through the the that particular element on your computer every second.

So if you hear about a here's a dinosaur. Let's say you hear about a five hundred mega hurts processor, that means five hundred million clock cycles per second go through that that CPU. All things considered, that's that's pretty fast, right. But you know, then we talk about things like a two point for gigahertz processor that's two point four billion clock cycles per second, much faster, which is even much faster, and they get faster than that obviously, But that's so

so when we're talking about processor speed. We really talking about the amount of work a processor can do within a certain amount of time, and faster processors can do more work in that in that time frame. So the five hundred mega Hurts processor can do five hundred million, uh can not five million tasks, but can use five million clock cycles toward tasks in a second, whereas the two point for gigahurts does two point four billion clock cycles toward tasks in a second. So yeah, that's that's

essentially the speed element. Now, UH CPUs are not the only thing that work on cycles, by the way, just want to make that clear when we do talk about clock cycles. Other elements like memory and IO devices also operate on cycles. And all of this is controlled ultimately by the motherboard. Yes. Now, if you're wondering how a you know, how they come out with these chips, UM, Well it's it's it's sort of controlled. Um. If you think about it. Let's say, let's take Jonathan's five mega

Hurts processor. UM, the manufacturer has, you know, knows something about the range at which this chip can operate. Um, it can operate more slowly than that, it can operate more quickly than that. But what goes on is in the process of building this and testing this chip, they know roughly about how much electricity it's going to use and about how hot it's gonna get. Um. Many many of us UH have an idea of what happens when

your computer overheats. UM. It will seize up eventually, UM and decrease the operating life of the computer overall too if it gets too hot too frequently. Yeah. So the thing is the the manufacturer of the processor is going to go, well, okay, this is this is a good range. This is about what it's gonna do. And essentially, yeah, and essentially it'll runs as fast as this without going nuts and requiring you know, a A to be immersed

in liquid nitrogen to keep it cold. We'll get to that right, right, So this is under normal operating conditions. This is about how fast this chip is going to run. Let's say it's five hundred mega hurts and and there are instructions UM in the computer actually written into ROM that will keep it from doing more than that. Yeah. Essentially,

you've got two elements that determine the speed. You have the motherboard which provides a baseline speed, and those tend to be around one, three, one sixty six or two hundred mega hurts, and then you have a multiplier on the CPU itself. Right, So for the five hundred megahurts machine we were talking about, the multiplayer might be five, and the motherboard provides one hundred mega hurts. So the clock inside the CPU is going to run at five

times the speed of the clock on the motherboard. So the motherboard sets the pace, the CPU multiplies that pace, and that's where you get your processor clocks need So the five multiplayer times the one hundred mega hurts, that's where you get your five hundred mega hurts. Now if you had a a multiplayer that was say twenty four times one hundred, well that's where you get the two point four giga hurts because you get the two thousand, one four hundred, and then that two thousand, four hundred

mega hurts is the same as two points for gig hurts. Um. So the multiplayers tend to be difficult to change with most processors, not all, but a lot of processors have the manufacturers have locked down that multiplayer in order to prevent people from pushing it too hard and causing problems down the line. Yeah, because Ultimately, the majority of us are going to buy our computers. We're going to set it up, do our work on it, play games on it, do whatever it is that we're going to do on it.

And the point is we wanted to last. Most of us can't just go buy a new computer. And if we don't know what we're doing as far as over clocking, um, you know, we're just gonna we want this machine to last us a good long time. And if you use it under normal circumstances, unless the fan breaks or some the cooling mechanism breaks. Even in computers with no fans, let's say, uh, you know one of the older Imax that they made a point of putting no fan in.

If you clogged up the air vents with something dust, a blanket, it will overheat and the computer will die or it will shorten the life of it. Um, so be un study an old crash a lot, that kind of thing. So to the point of the manufacturer setting a clock speed a default clock speed is is basically to make it a motherboard, a chip on a motherboard that it's gonna last the average computer user a good long while years hopefully, I'd say that's the that's the point.

I'd say that's true in the majority of cases. There are a few cases where manufacturers have developed one chip to go in a line of computers and have it in essentially a a an artificial limit to how fast

that processor can go per model. So let's say that I've got a selection of computers, um, and we're gonna say we're gonna call a Model A, B, C, and D, and all four of these have the same processor in them, but I've put limitations on it so that Model A can only go at five hundred mega hurts, and Model B as a giga hurts, and and Model C as two gig hurts, and Model D is like two point four giga hurts, and two point four is really where the sweet spot is. But I've put in these artificial

limitations on the previous ones. The reason for that would be I only have to manufacture one chip, and I can create devices for multiple markets. Because there's some people are gonna be out there who are saying, I need a computer, but I don't need it to do the latest stuff, or I can't afford to buy a computer

that has like the top level technology in it. But I'm gonna go and get this base model instead, and then they're going to be the up people on the other side of it, saying I want the fastest machine I can possibly get, so they're gonna go for the other one. Well, they can create a whole range of computers meeting all of these demands using the same chip if they put those limitations in place. And in some cases you can't really get around the multiplier limitation without

some really deep knowledge and risking ruining your computer. However, what you can do has changed the rate on the motherboard itself, and you do that through the BIOS system. And before we before we get into technical detail, um, overclocking is the process that we're talking about. Now. This means that you're increasing the limit at which the chip can process instructions. Yeah, it's essentially pushing more clock cycles in per second than what the chip was recommended for.

And we should say it really is a recommendation because uh, like so saying most of these chips, I mean almost all chips that come out have the capacity to operate over what they are rated for. So at two point four gigahertz processor can actually work faster than that. In fact, usually it's around five to ten percent faster than what

the rating is for. So if you are still five to tempercent faster without running the risk of causing damage to your computer, so you might be able to boost your computer's performance by or at least the processing speed by five or ten percent without having to worry about additional concerns. Once you go beyond that, then you have to start looking into creative ways of managing your computer so that it doesn't you know, just crash on you.

And even if you do just overclock your computer a little bit, there is a chance that stuff will crash because sometimes programs just don't work very well with overclocked processors. Um. Yeah, So that's the basis. Though. Overclocking means that you're pushing through more clock cycles. Second and uh, before we again, before we get into too much detail, this is not the kind of thing that you want to do casually and figure, oh, you know what, let's just go and

try this. You want to think about how what happens if it doesn't work, because if you don't follow the instructions carefully. Um. And we're not going to give you a lot of instructions because there's a lot of depend upon what the processor is so yeah. Yeah, But the thing is, if you're not very careful, you could damage your computer permanently. And most of the time, if you

try to overclock your processor, you're violating a warranty. So if you if you do damage your computer, you don't have any recourse to get it fixed by the manufacturer because they're gonna say, hey, you did this thing you weren't supposed to do. Therefore, we have no obligation to help you out. So so if you do this, make sure you you put some thought into it and make sure this is something you feel up to and that you're you're willing to try before you really give it

a shot. If you want to. Uh, it could be very very profitable for you if you're looking for a faster machine and you have the uh, the ability, and the you know, the money if you need it. But we can get into that now, right right. And the reason why you would want to overclock your machine in the first place is that it allows you to run more advanced programs at a faster rate without having to buy a new processor or a new machine. That's that's the big attraction for a lot of gamers out there.

They'll they'll buy a good gaming rig and then they over clocked their processors so that they can run games at at the highest settings without any slowdown and to have you know, the best performance in their game. Uh. And also it means that you know, they they're essentially getting higher like they're getting the equivalent of a faster processor,

but they're buying a less expensive one. Right. So if there were say a two point eight processor out there, in a three point two processor out there, and you knew you could overclock your two point eight so that would equal or exceed the three point you say, well, why would I spend the extra money getting the three point two when I could get the two point eight and just over clock that puppy. And of course there's the maker's reason because they can. Yeah, yes, there's always

that too. It's just like, hey, I I have the ability to fiddle with my computer settings. Gosh darn it, that's what I'm gonna do. Chris and I have more to say about over clocking a CPU, but first let's take a quick break to thank our sponsor. So you were talking a moment ago about the BIOS Basic Input

Output System. Yes, now, this is a part of When you boot up your computer, it goes through the BIOS set up, and part of that BIO set up is the motherboard checks the processor, sees what kind of processor it is and what the recommended settings are, and then goes into that recommended setting. For the speed that the motherboard provides is later on multiplied by the processor. Uh. The thing is, you can actually interrupt the BIOS set

up system and manually change those settings. So let's say that it was set at one hundred mega hurts, you could up it up to one thirty three or one sixty six or two hundred. Although you know, the more you boost this the the closer you ride that dangerous edge of possibly ruining your machine. It's like like getting in a car and pushing it faster than it was

meant to go. It can start to shake apart. Yeah, most of the instructions I read in the process of doing research for this podcast suggested that you would tinker with the multiplier and basically, rather than going how high can I push this up? Start it all the way up, what they suggest doing is taking it up a couple of notches. Essentially, again, read the instructions carefully for for the the system that you have, and then and the

materials that you've got on hand. But I'm oversimplifying. For the case of explanation, you might crank it up a notch or two notches and test it, see how it runs. Does it look like it's doing all right? Does it look like it's behaving oddly? If applications all crashing, but you might need to crank it back down again. Yeah, And and like I said, not all multiplayers are You can't mess with all multiplayers. It all depends on the processors.

Some of the processors are locked, so you that you can't do that, in which case you your only recourse is to change the setting of the motherboard as opposed to the setting on the processor. And also some motherboards you cannot do this through a software approach. You actually have to use a physical approach. You have to change these components that are called jumpers, which that will uh

will limit the motherboard speed. You have to you would have to physically replace those, which requires opening up your computer case and taking stuff out and changing stuff out, and that that can get a little utimidating for folks. It's a little bit simpler when you just hit a couple of buttons and then change some numbers on the screen,

But that might be necessary depending on the motherboard. A lot of the stuff about personal computers depends heavily on the specific hardware you have, which is why if you ever think about building a machine, you should really do some research and make sure that you know what components you're getting before you you jump into it. Because not

every processor is compatible with every motherboard. So if you were to just try and create your own computer, build your own computer, and you just you know, you were buying whatever was on sale, you might discover that, oh, I got this great motherboard and this great processor, but they aren't compatible with each other, so I can't actually build a machine out of it. Well, the same sort of thing with overclocking. You just you know, they're different

limitations based upon the actual hardware you have. And of course, uh it might involve depending on what you're doing, you might have to play around with the amount of voltage uh necessary to run the dangerous to Yeah, well, I hopefully there are our listeners when we start talking about the amount of electricity we're getting into um or any any measure of electricity, they start going, oh, maybe I don't want to do this without you know, really doing

some research. Um, I would very much recommend doing that if you are going to do getting into really messing with this. Um. But yeah, there it is worth noting though that uh uh certain boards are you know, certain processors I should say, come with the the ability to overclock sort of sanctioned. Yeah, they're built in. Intel has several chips that you can uh go into a specific screen and change the settings if you want to overclock

your processor, like the Extreme edition. Yeah, so that way, seriously, you can do like the turbo stuff, or you can actually knock up the processors bed you can change the multiplier a little bit, that kind of stuff. And uh, you know again this is you might ask, well, why isn't it like that just out of the box. Well, for one thing, not everyone needs that kind of performance. And for another, uh, here's the thing about processors. We've talked about heat a bit and about generating heat, and

too much heat can be a bad thing. When you have electricity running through a circuit, it generates heat as a byproduct. Some energy is lost due to heat waste. It waste some of its energy as heat. Yeah, so the more electricity you're pushing through. The more the more uh work you're making your system do, the more heat it's going to generate. And before long that heat might get to a point that's causing damage or or causing

malfunctions within the machine itself. So you have to figure out a way of dispersing that heat UM to handle that, or else your device isn't gonna work for very long. You might have the world's fastest computer, but only for a few minutes before it just of yeah, well, of course, there have been computers with no fans. There have been computers with multiple fans. It all sort of depends on on the guts on the you know, the stuff that's

inside the box um. And if you go to different overclocking communities, you can learn about the parts and bits that people uh seem to feel are the best. Now I saw a couple of fans listed as being excellent for overclockers because they're reliable and they push a lot of air UM. But depending on what you're doing, that may not be enough. You might have to go to say a water cooling system, which uh you know, water is a much more efficient dispersal of heat than than air,

is it dispersal. I'm making up words now or misusing them at any rate. So anyway, water is much better at taking care of heat than than air is, and so a water based cooling system can be very useful for people who are overclocking their their machines and they want to really push it to the limit. Yeah, I was joking about the liquid nitrogen earlier, but there are people who have some very elaborate liquid cooled computer systems.

And depending on how much you're you're pushing, especially if you have something like the again like the Intel chips are the A M. D S Black Edition chips where you can you've got the opportunity to really tinker with it. Um, you might do that. There are actually an over clucking competitions. Liquid nitrogen has been used to cool uh CPUs. Yeah, I'm just it's not the kind of thing that the

general public because it's all gonna have. You'm not gonna have a steady supply of liquid nitrogen to run through your machine constantly so that you can you can keep it going. But in any how have you seen my liquid nitrogen? It's not under the stage. Why do you need to know the uh uh where is my super suit. The uh yeah, but if you if you, if you don't have a stay supply of liquid nitrogen, then you know what are cooling or some other method is probably

the best for you. But during these competitions that the purpose of the competitions isn't to build the fastest computer. It's to to try and push the limits of overclocking as far as you can go. It's not that you're going to have a practical machine after you're done, right, It's just this is an example of a a an artist, if you will, an engineer really knowing the limitations and how to play with them and how to push things

to a super speed. So at ce S two thousand eleven there was an overclocking competition where they had several different phases and they were overclocking things not just CPUs but also graphics processing cards because you can do this with various components, not just CPUs. It's just that's what we tend to think about when we talk about overclocking.

But in this competition, they took an I seven nine nine X Intel chip, which normally runs at three point three three giga hurts with a turbo speed capable of points six giga hurts. That's pretty darn fast. They overclocked it to five point nine three five giga hurts, so nearly six giga hurts of of clock speed. UM, and that was using some pretty phenomenal cooling mechanisms. Uh, not something that the average consumer is going to have at

his or her fingertips. Not the average consumer. Maybe maybe if your last name is do find Schmirtz, you might have something. Well, yeah, but that's all coming from the alimony my coldinator. Hither guys, it's Jonathan FROMT the Future. I'm just gonna have us take another quick break to thank our sponsor. When you overclock your process or, it does require that you tweak some other settings on your computer, including the ram UM. So keep in mind that this is not a a if you're just sort of I

thinking of tinkering with it just for the fun of it. UM. Keep in mind that once you start messing with one part of it, you might have to tune some other factors relating to your your computer's operations. So uh, make sure you do a bit of reading about the processor you're using, UM and the other equipment, the ram the type of ram UM. You might even check out your GPU. If you're feeling bold, you might even try to overclock

your GPU again. This will also increase the amount of heat. Um. So you this might be a good time to uh move your computer to a small bard in Norway where it is where I'm told it's rather chilly. Um. But the people of the seed vault are be coming. No move it down there, making the seeds warm up. But so yeah, it's quite a bit of there's quite a bit of tinkering that could be involved with this that you know. It's not just a oh well, I'm just

gonna turn this one up to eleven. Yeah, there are a lot of resources out on the net that will help you out if you want to try this. And really the nice thing is there's so many that are out there that you've got a good chance. If you just plug in whatever processor you have and the word overclocking into a decent search engine, you will probably get some returns from people who have gone through this process and they can tell you what worked for them or

what you know, what things to avoid um. And like I said, there are a lot of communities out there on the net that have just full discussions, like full message boards just dedicated to overclocking and the different techniques that they used, and uh, you know, some of these might be a little technical and might require a little bit of backtracking so that you can really understand the the subtle, the subtleties of what it is they're saying.

But but it's totally doable. I mean, in most cases, it's doable without you ever having to crack open your computer, which is the best part, right, you know, because you every time you have to open your computer and take stuff out, that eliminates a significant percentage of the people who would have tried it otherwise just because it's either too much of a hassle or they find it too intimidating. Um two things though, to to make sure one that

you don't make assumptions on similarities. That was one thing that that I read that if your computer, if you're reading information reform about overclocking, you're getting ready, you're you're gotten the bug. You're seriously thinking about this now, and that you're reading a post by someone who's done it, who's who's got a chip that's a little that's just a little different than yours. Don't go by that information.

They said that um from from what I have read from people who have written instructions on so you want to overclock your computer, well, here's what you should do. That was one of the things that I read several times was if you've got something that's very similar to what you've got to the instructions from, don't don't go by strict similarities. Make sure that you are going by someone who knows instructions based on the specific stuff that

you're using, because similarities aren't good enough. When you're messing with this, you could seriously damage your computer. And uh, that's the other part. Make sure that you're really willing to give this a try, knowing that you might really muck things up for the insides of your machine. Yeah, if you're careful, you probably don't really need to worry

so much. But it's good to have in the back of your mind because otherwise, you know, if you you know, if you do the typical what we like to think of as the typical American thing, we're more equals better, right, you might be Let's Craig get up to eleven and the next thing you know, your machine doesn't do anything anymore. It's not it's not doing anything faster than any machine you've ever had. My computer does nothing at the speed

of light. It works great as a doorstop. No, I'm sure that there will be somebody out there who's listening listening to this podcast who has had experience overclocking, and they're going to write in and say no, Jonathan and Chris, it's easy to overclock maybe for some people, but for some systems and for some systems, but um, you can't. You can't. You can't apply that universally across everybody. And uh, and it's it is possible that if you're not careful,

you could damage your computer. And if you don't have a need for overclocking, if you're not playing lots of of of high like resource demanding games or or other applications that just require a lot of processing power. Um. I mean, it could be a fun experiment if it's something that you just want to try and get your hand in, and especially if you have like an old machine lying around that you don't really care about and you just want to have the experience of overclocking something,

that's fine. But if you don't really have a need for it at all, I really don't see any reason to do it because Ultimately, if you are overclocking your machine to really push its limits, that is, it is not just a time investment, but it is a money investment too, because you will have to find some way to address that heat problem. And that concludes this classic episode of tech Stuff. I hope you guys got to learn a little bit about clock cycles and over clocking,

and like I said, things change. CPUs and GPUs are much different. I mean, they work on the same general principle, but they're much more powerful than they were in two thousand twelve. And thank goodness, because otherwise I would never be able to play pub g at all. Anyway, I hope you enjoyed this classic episode. If you have any suggestions for future episodes of tech Stuff, send me a message. The email is tech Stuff at how stuff works dot com.

Drop over to tech stuff podcast dot com. That's our website where we have other ways to contact us plus information about the show. There's also a link to our store over at t public dot com slash tech Stuff. Every purchase you make goes to help the show, and we greatly appreciate it. And I'll talk to you again really soon for more on this and Fathlands of other topics is that how stuff works? Dot com m