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Ron Bakker
28-08-2003, 08:40 AM
I still havent quite figured it out.
let say we have a cpu of rating at 2 gigahertz, ok that means frequecy of operation, as in two billion transistor switch times a second.
So why is the front side bus a different number??
Or am I looking at this in the wrong light.
Cheers Ron

robo
28-08-2003, 08:51 AM
I am guessing on the FSB, but the gigahertz is the clock speed, which doesn't always relate to operations a second (as some take two or three cycles, maybe more).
The frequency of the FSB is to do with communicating with peripherals (memory for sure, possibly PCI cards too, that bit I don't know). As the rate of transmission through the bus is critical to how much work the CPU can do, the speed is important. However, it is just data transfer, not actual processing.

The tuning of a PC is like a car. The engine may be V8 but with a Morrie thou gearbox, wheels, diff, etc, it isn't going to go very fast. All parts need to work at a similar level, or they all are limited by the slowest component.

Does that help?
robo.

Murray P
28-08-2003, 09:16 AM
Here is an analogy and, this is my understanding so I'm open to correction.

Think of the cpu as the mail centre of a city, the central post office, eg Wellington Mail Centre in Petone. Theres a motorway that runs from Upper Hutt to Wellington and up the Gorge to Paramata, you main bus. There are subsiduary roads to post boxes and letter boxes all over the place that service various suburbs and specific adresses for receiving information (some are residential, some are industrial or commercial).

The roads and motorways have a limit to their traffic capacity and the vehicles that travel on them have a limit to their carrying capacity and the speed at which they travel at (FSBmhz). NZ Post send out trucks and vans to pick up the mail from the post boxes and deliver it to the Mail Centre (cpu) where it is processed and then sent on its way to the various destinations. The number and productivity of the workers sorting the mail is your processor rating, they're also shift workers and work in cycles the no of cycles they work is related to the rating. These guys just don't look at the address they open the and read the mail as well and do other unmentionable things with it ;). Some of this mail is an answer in itself and some will require a reply so, the process will start again.

Is that clear?

Cheers Murray P

PS. Corrections are welcome. What about ram and storage?

Ron Bakker
28-08-2003, 09:04 PM
Yes I think so.
So when I move mouse click the cpu requests somthing from the hard drive, which sends the required info into the cpu which proccesses the info then sends it to the ram. But in the case of a game being played, does let say a texture get sent straight from the ram to the vid card or does it have to go throught the cpu first.
Oh bye the way thanks for your help sofar Murray'n'co

Ron Bakker
28-08-2003, 09:07 PM
Re Robo
However, it is just data transfer, not actual processing.

Good point

forrest44
28-08-2003, 09:47 PM
I think the FSB is slower because it is 64 bits (or something) and the cpu is 32 bits.

I'm not sure though.

Cheers

-=JM=-
28-08-2003, 10:29 PM
Processor speed = FSB * multiplier.

Eg. my 1900+ (1600MHz) has an FSB of 133.3333 and a multiplier of 12.

Murray P
29-08-2003, 12:34 AM
Your ram is very important to the whole bizzo. Requested data gets loaded into ram which is much faster that your storage (hard drive) so, generally a chunk is loaded, not just what is immediately needed. When the amount of ram you have connot handle all the requests/data rerquired thats when things start to goo ssslllooowwww, your hard drive starts chugging because its trying to load from virtual memory which is reserved for such tasks in anticipation.

How am I going folks, I've not tried to explain this before and not thought about the ins and outs. I think I'll take a breath and get back. If you can't wait for the next riveting installment of Murray P's How To Murder A Subject, have a look here (http://www.techtutorials.com/Hardware/)

Cheers Murray P