My PC currently has a P4 2.66GHz CPU on an ASUS motherboard. It is rated for as fast as PC 3200 RAM (per their web site). Currently, it has 512Mb of PC 2100 DDR RAM installed.  I want to upgrade to 1Gb of RAM. My question is, must I use PC2100 RAM with this CPU, and just install another 512Mb PC2100 RAM module, or can I replace ALL of the memory with faster (such as PC2700 or PC3200) modules? Would I have to make the bus speed change in BIOS or would it automatically be detected?  Would it be worth it in terms of performance to upgrade to faster RAM (and bus speed, which currently is 566Mhz266Mhz)? Does CPU clock freq have any effect on bus speed?

This should be easy stuff for a `puter person, which I'm not.  Thanks in advance!

ETA: Question resolved.

ram is cheap.   take the old ram out and buy all 3200 ram.   if you bought 3200 ram it would only run at 2100(if you left the old stick in).  

you will be much better off with the new ram, at the same speed.   crucial, and corsair the the brands i use for my systems

So you're saying that the bus speed will be determined by which type of RAM I install? The CPU speed has no effect? If so, I'm there! If after installing 3200 the bus will still run at 566Mhz, I might as well just install another 512M of 2100.


Also, this PC is a couple of years old, saving a buck here and there until I replace it next year is a consideration....

your bus speed will not change.   to get full speed of the system you should have 3200 ram installed.  there should be very little prices difference between 2100 and 3200.  



edit

on crucial you can get a 512mb 2100 or 3200 for 71.99 plus tax

I guess I'm missing something. If by installing all new 3200 RAM the bus speed doesn't increase (vs the old 2100), how does the 3200 memory improve performance? (My first post said 566Mhz, should have been 266Mhz). 3200 runs at 400 Mhz. So does the 3200 cause the bus to run at 400Mhz, or will I need to go into the bios to change the  bus speed? If the bus will still run at 266Mhz no matter what, I see no need to buy a whole gig when I can get 512M for half the cost. If I can install a full gig of 3200 and be able to increase the bus speed I'd go for it.


ETA: Further research has revealed that I do NOT have an ASUS MB, and the one I do have is rated only for PC1600 or PC2100.  Guess that kinda helps my decision...

well in your first post you said  566,  i figured you ment 533.  so in this case.   so since its only 266.  2100 would be the best way to go

you would not get a performance increase getting the 3200.

Thanks for the help!  I screwed up and thought I had a different MB, and now it looks like I have no choice anyway. Good thing I checked - 2100 is almost obsolete!!  

It can sometimes lead to stability problems when mixxing and matching ram moduals. Buy a pc3200 1gig stick for best results.

*sigh*


The P4 2.66MHz has an effective FSB of 533Mhz (really 4x133MHZ).


Adding anything more than PC2100 (2x133MHZ) is a waste of money.


Intel chipsets will not run the system memory clock faster than the FSB clcock.

Quoted: *sigh* The P4 2.66MHz has an effective FSB of 533Mhz (really 4x133MHZ). Adding anything more than PC2100 (2x133MHZ) is a waste of money. Intel chipsets will not run the system memory clock faster than the FSB clcock.

Already ordered 512M of PC2100.  Just trying to speed this old box up a little for the remaining year or two it has left.

If you buy RAM that is rated faster than your motherboard, the RAM will simply run at a slower speed to accomodate the motherboard.  The "too-fast" RAM won't speed anything up.

I typically just get the fastest RAM that my motherboard will take.  On some systems, I might find a better price on the faster RAM, so I go with that.

512 Mb of PC2100 installed, running great, enjoying new speed!

Thanks for the help all!