Processor FSB faster than RAM? - Ramifications?

What happens if I have a T2400 (667MHZ FSB) and 2x512MB DDR2 533 MHZ RAM? I know that in the inverse scenario, the RAM would clock down to the CPU's FSB, but in this case does the CPU just run a bit faster than the RAM? Would I be better off value-wise going with the 533MHZ FSB T2050 ($60-70 less)?

 

The RAM would run at 533MHz, but the FSB would still run at 667MHz. Depends on what you are going to do with the notebook - the T2050 should be more than enough for most people.

 

More than likely, the CPU would run at less than it's rated speed. Normally the T2400 is a 1.83GHz processor. 1833/166 (one quarter the DDR 667 clock speed) = 5.5. So the multiplier is 5.5x. If you stick it on a system with a 533MHz bus, it will run at 133 * 11, or 1.46GHz. I don't think you want to downclock your system that much. Go with the 2050, or go with the 667MHz RAM. Make sure they match to get good performance.

Edit: Oops... looked at the Wikipedia article on Intel dual-core processors and fixed the multipliers above accordingly. The concept still stands, and the resulting clock speeds for the processors I came up with were correct.

 

No, that is not the case. The RAM will run at 533MHz and the FSB will continue to be 667MHz. The RAM will only sync with the FSB if it is capable of running faster than/equal to the bus.

Also the Intels FSB are all quad pumped, meaning the original bus speed for a 667MHz FSB is 166MHz. The multipliers are derived from this.

 

Ahhh. Memory will run off-kilter from the CPU FSB speed? All the systems I've had they've been tied inextricably (as well as to the PCI bus speed, etc. so you couldn't overclock the bus speed without throwing PCI rates out of whack and such) I guess they are putting more clock-generators in chips nowdays.

 

This is why they have systems with ddr333 ram and a 400 mhz fsb (my old averatec turion system). But the ram running at a lower speed is a bottle neck, but for the life of me I couldnt get ddr400 to work without bsod, as well as anyone else.

 

the memory multiplier keeps the FSB the same even though RAM is slower.