Questions regarding PC CPU

yihung (yihung@home.com) Sat, 2 Dec 2000 13:05:51 -0800 

From: "yihung" <yihung@home.com>
Subject: Questions regarding PC CPU
Date: Sat, 2 Dec 2000 13:05:51 -0800




Hi,

here's my question (s)

the page 2 of notes 'microcomputer architecture', when it says "The clcok speed typically ranges from 32kHz... to several hundred MHz (for fast, typically computationally -intense applications)"

1) I assumed that 'fast, typically computationally - intense applications' refers to desktop PCs. So the question is: 

PC CPUs ' speed is comprised of it's bus (front side) speed multiplied by it's internal clock speed, and the clock speed is usually referred to the 'multiplier' which comes in 3,4,5,6,..etc.. no more than 7 that's useful for modern PCs. For example, if you have a 600MHz cpu, that means most likely, the bus speed is 100 MHz with internal clock speed fixed at 6. So, is that clock speed mentioned in the notes same as the internal clock speed I mentioned? (apparently it's not) , then is it referring to the speed of the CPU? (the 600MHz)  Or am I mistaken with the whole thing?

2) If I'm not wrong, CPUs can read, write, and when it's not doing either, it's in an idle state.  Usually when I load up my PC, and after every application is loaded, windows tell me that the System Idle Process is running and the CPU usage is at least 94% for about a minute or so.

Question: during idle state, the cpu isn't doing either reading or writing, why is it being used so intensely? Is it simply because windows refer system to be idling when actually after loading applications (after a reboot), the cpu is still processing something else that's not applicaiton related? say memory dump etc? (or does memory gets dumped before computer shut down?  <---- question 2.5 :) )

3) this is a bit off topic, but I kinda wanted to have someone verify or correct this:

Modern monitors can show at least 256 colors (up to 32 bits), and I believe that what color to be used is instructed by the graphic card (which is told by the cpu?), So, does the graphic card have a unique set of binary numbers for each of 256 color pallet?


Thank you for your time.

Yihung Kuo