CPU, FSB??

I am a little confuse about the effect of the FSB on the processing power. Assuming that I have the same proc at the frequency but different FSB ( and multiplier), would I see any diferrence in the computing power? Assume that the memory also runs at the same frequency.

Pasoleatis

Thank you for the answer. I understand app how is thething with base frequency and multipliers. I was wondering if there is any difference in running a proc at same frecquency, but with different FSB (of course it would have also differnt multiplier).

I want to buy a custom laptop which is built on Clevo D901C. I know that the chipset supports only 1066 MHz FSB, but some company oferrers the Qx6800 on it at 3Ghz. I was wondering if the proc is working at its full capacity or should I wait for other versions of the laptop which has a chipset with 1333MHz.

According to ebuyer the QX6800 uses a 1066MHz BUS.. @ 2.93GHz This would indicate a 266MHz FSB (Quad) using a x11 multiplier at default. Therefore the QX6800 advertised is basically set to default capacity.

further info: http://techreport.com/articles.x/12210

Raising the FSB is the only way to overclock most processors, as the multiplier is locked. Years ago, even if you had a processor that you could unlock the multiplier on, raising the buss speed resulted in better performance than just raising the multiplier, as buss speeds were realitively low. The buss is what your processor communicates over to the rest of the components in your PC. So raising the buss speed results in a larger overall performance gain than raising the multiplier to achieve the same actual speed.
Today's processors run pretty high buss speeds already. Raising the FSB speed does not result in a significant increase in speed over just raising the multiplier(if you could somehow unlock the multiplier) But, as I said, most CPU's have the multiplier locked.
For instance,
100Mhz buss X a multiplier of 10 gives you a 1000Mhz processor or 1Ghz.
If you could unlock the multiplier, or go with a higher FSB, here are 2 results.
100Mhz FSB x12 gives you 1.2Ghz
120MhzFSB x10 gives you 1.2Ghz
The second senerio would result in higher performance.

I stress again that this is a fact of years gone by, the buss speeds that modern CPU's run at are high enough now that raising the buss speed vs raising the multiplier does not have much difference in overall performance. (although it still does have some impact towards better system performance) The buss used to be the main limiting factor of PC performance, hence the move by manufacture's to raise the buss speeds and lower the multipliers to achieve the same final speed on modern processors.

I see. So this FSB is in a way similar to the bands of a highway. So the FSB is important also when the proc comunicates to the memory, hdd, video card or other components?

Actually the quad pumped part would be more similar to a highway in lanes.

The FSB speed, is simply setting the highway speed limit.

Edit: or somewhat a visual:

Lane one-------->speed limit 266
Lane two-------->speed limit 266
Lane three-------->speed limit 266
Lane four-------->speed limit 266

above total-------------------------1066
multi--------------------------------10x266

Actual speed-----------------------2660 mhz or 2.66ghz