Can I use PC2100 RAM in a comp with PC2700?

davetrousers

My old computer has died. It originally came with 256MB of 2100 RAM but I added an extra 512MB stick to make it 768MB.

My GF's computer only has 256MB of 2700 RAM. Could I use the 512MB stick of 2100 RAM in her computer so it has 768MB of RAM?

Thanks

hobo28

It depends on your motherboard. Ideally you should stick to the same speed RAM. If the motherboard allows you to, force the memory to run at the slower speed.

However, you won't do your computer any physical harm by trying it so my advice is go try it and see.

davetrousers

Thanks, so if it works it will be 768Mb of Ram BUT running at the PC2100 speed? (Approx 270MHz I think! rather than 333MHz)?

Do any BIOS settings need changing?

weegie.geek

Possibly. Depends on the motherboard. Some boards will tie the CPU's FSB to the clock speed of the ram. If yours is set to do that, you'll either have an unstable pc, with pc2100 being forced to run at 2700 (this might work, mind you. some ram will happily manage this) or, more likely, your cpu will slow down to a 133mhz fsb, assuming it was running at 166 in line with the ram before.

You CAN run the CPU and ram asynchronously in most cases, without problems, and while you might not notice the difference between your ram running at 133 and 166, you'll almost definitely notice the difference between the processor doing the same.

I'd definitely check what processor it is, what FSB it can do, and manually set the memory clock and cpu FSB to the appropriate speeds.

ormus

most mobos will run the ram ok but at the lower speed.
you can mix ram but its not really advised. you might find some weird effects after a while with some progs.

STEG_2

Reading your question would it not be advisable that if your MOBO can accept 2100 speed RAM, which is likely you remove all the RAM from your "dead" system and place in your GF system.

Then the 256 2700 issue will not exist as the RAM will both be running at 2100, and the extra 256 2700 from your GF can gather dust or sold on.

weegie.geek

Or assuming there are three or more slots, have 1GB.

davetrousers

STEG wrote: »

Reading your question would it not be advisable that if your MOBO can accept 2100 speed RAM, which is likely you remove all the RAM from your "dead" system and place in your GF system.

Then the 256 2700 issue will not exist as the RAM will both be running at 2100, and the extra 256 2700 from your GF can gather dust or sold on.

Good idea. Thanks

Three times the MB of RAM operating at a slower speed is better than 256MB running faster.

GunJack

You could check out what your motherboard is capable of using by going to

http://www.crucial.com/uk/?gclid=CMeuwc21kpECFQljMAodWSVjGQ

and letting their system scanner to it's stuff - it will tell you what your MOBO can handle.