question about FSB and memory speeds
 

ok my friend is trying to do a mini upgrade on his comp...he wants to use the memory that he has now (PC2100 DDR266)...

ok he wants to get an AMD cpu with 333FSB and obviously the memory operates at 266. If he sets the mobo to 266 and keeps the memory at 266 - he will obviously have to clock the cpu to 266. this will actually lower the core clock of the cpu right? also, would it be ok to compensate for this by increasing the multiplier?

Umm, this makes no sense to me at least. Your "friend" would be essentially going backwards here in his pursuit for "speed". Memory is cheap really cheap, at least compared to a new mobo and a new CPU.

Yeah, the FSB of the CPU will run at 266 MHz if the RAM is only 266 MHz. Actually, to get a bit more technical, the CPU will stay at 333 MHz but no performance increase will be seen because the RAM is only operating at 266 MHz. In other words, the synchronization is no better than before with the system bus running at 266 MHz because of the RAM. He can raise the multiplier if his CPU is unlocked, but remember that raising the multiplier will only take you so far performance-wise...it'll actually decrease your performance after a while. The CPU won't lose any clock speed but the FSB will be useless because the RAM is only running at 266 MHz. There's honestly no reason to buy a 333 MHz processor unless you're gonna buy new RAM as well. The increased FSB of 333 MHz is one of the main boosts of an upgraded processor...negating this will make the new processor useless. His best choice is to suck it up and buy some new RAM. You can get 1 GB of PC2700 for around a hundred bucks.

-Lasereth

Couldn't have said it better.

thanks guys...i realize that my question made little sense, haha. he is going to suck it up and buy some better stuff. he just "found" some extra money, so athlon xp w/ 400mhz fsb and pc3200 memory. easy enough :)