Subtitles of the Movie

Clock speed is very important to the operation of your PC and the CPU. And let's talk about clock speed a minute. Simply put, clock speed is the drummer for the PC band. Think of all the components being members of a band. The clock speed is the drummer. It keeps everybody on time. Okay, everybody on the, on the motherboard has to be in sync with each other or these things aren't going to happen properly. Okay, now the clock speed is the method that allows the CPU to know when one task is completed and another one is beginning. Okay, let's go back to that diagram that I used in another video about the CPU itself. Let me go find that for you. Okay if you remember this diagram from another video, if you remember the little man inside the CPU carries on tasks that we have to push in information by turning on lights to tell him, okay, if you remember this one was binary 010100, or binary 10, and this tells him that he has a little look up list in there and a binary number of 10 tells him to do something. Well, first of all, ah, we need to know, we need to tell him, Okay, here's where we start. If you ever had a CB radio, you know, you would, you would start talking and you end with over, or out, or ten four, any of that kind of ah stuff that seems hokey now, but we have to tell him in there when things are starting and stopping and so what this, the clock speed does, or the clock, it gives us kind of a metronome, kind of a start, stop, start, stop, start, stop, and this keeps everybody in, kind of in timbre with each other and, and ah on tempo. Now, what is the, where does this pulse come from that does this? Well, there's a clock wire on the bus and it's only job is to transmit these ticks, or this metronome if you will. For those of you who are in music this is, there's a lot of music analogies here. And this transmits these begin and end messages. Okay, here's the start, here's the stop, here's the start, here's the stop. I'm over simplifying but I want you to get this picture. Now, where does the signal come from? It comes from a system crystal. This is a quartz oscillator usually that's, that's attached to the motherboard and this thing sends out messages. Now, the reason it's attached to the motherboard is because we just want it to send out a steady beat, and then we will allow the RAM, we will allow the processor, or anything else to apply multipliers to it so that they can run at whatever speed that they want to. But they're still connected in time to the system clock and to everything else on the motherboard. Now, if you're a musician, if you've ever had any music theory you know that we can have a beat, drummers do this all the time, the beat may be one, two, three, four, one, two, three, four, but the guitarist may play in like quarter notes or eighth notes, okay, and so while the beat's going one, two, three, four that instrument's applying a multiplier to the beat and they're playing like one and two and three and four and, okay, so they're going faster than the regular beat, but they're staying on tempo. And that's exactly what's happening. Now the true definition of clock speed, you will hear a CPU's clock speed represented and that is the maximum number of tasks that the CPU can complete within a designated amount of time, usually expressed in a second. Now, the CPU doesn't necessarily always run at it's maximum speed and there's a lot of reasons for that we won't get into right here. But here's something interesting. The Intel 8088 had a clock speed of 4.77 megahertz, okay, that meant that it could do 4.77 million tasks per second. This was its max, okay. So, picture, if you would, the tempo of, of the particular actions, 4.77 million times a second this beat was being sent out. Today's processors are as fast as 3 gigahertz; that's 3 billion tasks per second. Now that's quick. Now back to the diagram. One of the things that we, we're going to make sure this with this clock is, is that across the bus and really I should have one more wire here that takes care of keeping up with this pulse, and let me add this here because we're going to get into it when we talk about RAM a little later in the course, the RAM is also attached to this clock speed because at the same time that we want the processor in tune with what's going on out here, we also want him in tune with the RAM memory so he can read and write stuff along with everything else. And so, that's what's happening there. Now, a couple a questions come up when we talk about clock speed. Why do some processors have different clock speeds? Well, it has to do with the efficiency of the processor and just the way the processor's working. Processor manufacturers, for example, build every processor to be say 2 gigahertz, okay. However, some of the resistors don't work, some of the connections don't work, there's all kinds of things that can go wrong, and so that one will actually only clock up to 1.5 gigahertz, and so they sell it as a 1.5 gigahertz okay, because that's as fast as they can speed that thing, or clock that thing, and it worked. Okay, so there's that one. And then there's a, a situation called overclocking and if you're a nerd you can play with this and what this means is, and it's kind of like the old I Love Lucy episode where Lucy and Ethel are trying to put candy in the box and it keeps getting faster and faster. Let's say that ah, I want to ask you to run my processor faster than it was built to run. There's software and there's some hardware things that you can do to overclock and actually run it faster than it's supposed to. Now this is like driving your car 100 miles an hour when it was designed to cruise at about 70. A high chance that you're going to overheat that processor or damage that processor, but there's a lot of things that you can do and a lot of people play with overclocking, and you can get faster performance out of your PC. That's an advanced topic. You probably won't see that on the A Plus exam, but I just wanted you to know about it. So, that's what the clock speed is. It just keeps everybody in sync so that everything works together and the man inside the processor understands when the start and end of a particular set of instructions is.