pc memory processor speed difference?

[tali122]

pc memory is im told about the speed of the pc in multiple tasks and then im told processor speed is how fast the pc is- they both sound exactly the same to me- so WHAT is the difference? and i am correct in assuming the difference is not much

[vehelpfulguy]

Part 1

I will try and explain how the internals of a PC works and then you may understand the difference between a processor and the memory. 

I am going to talk about 3 main components inside a PC:- the HARD DISK, the PC MEMORY, and the PROCESSOR.

The HARD DISK is the slowest device, the MEMORY the next fastest and the PROCESSOR the fastest.  

When you install a computer program like Windows, or Word, or a PC game or whatever, the program is stored on your computer HARD DISK.

When you first turn your computer on the pc memory is empty. Your computer will then load from HARD DISK into PC MEMORY the software that it needs to run.

This will be Windows and other basic programs. If you then start another program, like say a PC game, this is also loaded into memory.  

So gradually your memory fills up with all the software you are running.    

If the memory become full (you try to run too many programs) then the computer copies parts of the programs from memory back onto the hard disk to free up some space.

But at some point the computer will need the part of the program that it copied to hard disk, so it copies it back into memory, while copying some other program out.

This process of copying software in and out of memory onto hard disk is called SWAPPING. Remember the HARD DISK is fairly slow device (relative to the rest of the computer) so the more swapping your computer does the more it slows it down.

So to stop your memory filling up, the more memory you have the better.

More to follow

   

[vehelpfulguy]

Part 2

So as I said, when your computer starts up the programs you need are loaded in to PC memory. But PC memory cannot actually RUN a computer program.

What runs a computer program is a PROCESSOR.

All computer programs are made up of instructions, and a program like Windows is made up of millions of instructions, some issued over and over again.

Now a PROCESSOR can only handle ONE instruction at a time, but it copes by doing MILLIONS of instructions a second. In fact processors are measured in MIPS (millions of instructions per second).

What happens is that the PC MEMORY, which is quite fast, and where the program you are running are stored, sends the instructions one at a time to the PROCESSOR, which does the instructions.

So obviously the faster the processor the more instructions it can do. The speed is measured in giga hertz (Ghz) so you see a processor speed listed as 3.3Ghz for example.  

Over the years memory has also got faster, so it is able to pass instructions quicker to the processor.

When you turn your PC off, all the work you have done is saved to your HARD DISK by Windows. Your processor stops working, and everything in your PC memory is lost, so it is empty until you turn the PC on again. 

So to sum up, the more PC memory you have the more programs it can hold before it starts SWAPPING. Nowadays Windows XP needs about 512Mb of memory, but the more the better.          

Also the faster the processor you have the better, because it can do more instructions a second.

[tali122]

thanks for your detailed answer i am wiser now :) but it does illustrate problems non-techies like me face from a jargon obsessed industry

[Space]

if your PC doesn't have enough memory, then it will be very slow, even if its processor is fast.
Once it has enough memory, it's mostly the processor ( and other components ) that will determine how fast it goes.