At this point, you may be wondering. If these input data, where is that data going?
And if these output data, where is that data coming from? Well just like with people,
the inputs are sending data to the brain, which then sends data back out through the outputs.
In this lesson, you'll learn about the computer's brain, along with several other crucial parts
that work together with it. All of which are found on the computers motherboard.
By the end of this lesson, you will be able to explain why the
CPU is so important for a functioning computer,
and explain the importance of other components on a computer's motherboard. Let's get into it.
The brain of the computer is the central processing unit, or CPU for short.
Remember how computers used to be huge clunky messes of transistors and vacuum
tubes and wires going everywhere, like ENIAC? But then the integrated circuit was invented,
which allowed all those big pieces to be created together as one small piece.
The CPU is one of the modern day results of that invention. The CPU consists of millions, or even
billions, of transistors on a teeny tiny chip, turning on and off repeatedly. These transistors
are what make the CPU capable of transmitting data and performing complicated calculations.
Remember Moore's law about the number of transistors doubling every couple of years? This
is what Gordon Moore was talking about. Computer brains essentially doubling the amount of brain
cells they have. Wild, right? Now when we say the CPU does calculations, we mean it. Everything the
computer does is just a complicated calculation. Computers perform mathematical calculations in
strings of code we call binary, represented by ones and zeros, and those codes tell them what
to do. For instance, this looks like math, but to a computer it says my name, Caroline.
It may not make sense to you, but binary is the only thing that makes sense to a computer. And
clearly it works, because everything you do on a computer is made up of binary calculations.
The CPU sends signals and does calculations so fast we don't even notice it.
Faster than that. Nope, even faster. It's so fast there's no way we could visualize it, no matter
how much we speed up this animation. The number of times the CPU can send signals to retrieve,
process, or store calculations every second is known as its clock speed. Clock speed is measured
in gigahertz, with one gigahertz being equal to 1 billion signals per second. The fastest CPUs,
at least for now, have a clock speed of 6 gigahertz. Check this out. In the one second that
just passed, those computers were able to do six billion calculations. Talk about a fast computer.
Now for the motherboard, the main focus of this lesson. The motherboard is a large board
full of circuits. All the components plug into the motherboard, and then the circuits carry
signals back and forth between the CPU and the other components. The CPU plugs in right here.
But what do all these other components do? These right here are PCIE slots, which are where
extra components that require high-speed data transmissions get plugged into the motherboard.
The most common uses for the PCIE slots are updated graphics cards and sound cards. Graphics
cards are responsible for outputting graphics to display devices, including screens and projectors.
Graphics cards work really hard to output amazing graphics and get really hot. So
they have built-in fans to keep them from overheating. Graphics cards also
include all the necessary ports to connect your visual output device to the computer.
Sound cards are similar to graphics cards, but for audio devices to plug into instead.
Sound cards include ports known as jacks to connect audio input and output devices.
I should note here that PCIE slots and the high speed components that use them, including graphics
and sound cards, are mainly only found in one kind of computer: the biggest kind. Desktop computers.
This is because graphics and sound cards are pretty big,
and the only computer that has that much empty space inside the case is a desktop computer.
In smaller more compact computers, like laptops and smartphones, everything is packed very tightly
with no extra space for upgraded components. So they usually don't even have PCIE slots. You
have to use the graphics and sound capabilities that came with the device. Laptops at least have
enough room to upgrade one thing: the short-term memory component, known as random access memory.
RAM for short. To help you understand what the RAM does, let's do a little activity.
Try to add the numbers 443, 763, and 532 together in your head. No writing
it down. No using a calculator, Just in your own head. Pause and do that now.
Okay, now I want you to do the same thing, but this time use a paper and pencil. Pause now.
The correct answer doesn't matter. What matters is how difficult each experience was.
Did you keep forgetting things while you tried to do it in your head? Was it easier the second time
because you didn't have to remember everything, since it was all written on the paper? That pencil
and paper you used is like a computer's RAM. The CPU does millions of calculations every second,
and that would be really hard to do without a place to keep track of these calculations.
So it stores that data in the RAM, its short-term memory, until it needs it again.
People upgrade their computers RAM because more RAM means the computer can remember more
calculations at once, and that means a much faster computer. Our last two components work
hand in hand: the BIOS and the CMOS RAM, two very small, very important pieces. The BIOS performs
functions that are so important they have to happen before the CPU even starts up. Things
like running the startup sequence so the computer turns on, or finding and connecting all the other
hardware on the motherboard, so the computer actually works. The BIOS is pretty important,
and the CMOS RAM is essentially the memory chip for the BIOS. Any settings that your computer
needs to know in order to start up are stored on the CMOS RAM. Now, regular RAM stops working if
the power is turned off. But it would be really bad if your computer forgot the date, time, and
all your settings every time it shut down. So the CMOS RAM is powered by its own special battery.
That way even if everything else turns off, the CMOS RAM stays on to keep your settings safe.
The motherboard has a lot of components. If you think we covered a lot in this video, you should
see the list of components we didn't talk about. Since this course is more about using computers
than teaching you how to build them from scratch, we won't get into every single part. If you'd like
to research more, we've included a list of other motherboard components in the PDF that you could
look into. One thing is still missing though. If a computer's RAM is only the short-term memory for
doing calculations, where is the long-term memory, so you can actually save things on the computer?
In the next lesson, you'll learn about the different long-term data storage devices
computers use, including hard drives and flash drives. Until then, remember. Your brain is the
smartest computer in the world. So keep it charged and never stop updating it. See you next time.