Ram upgrade Help

HELP!

Trying to help a friend out on their machine and cannot get 2000 to accept ram upgrade.
THe machine is an older home built machine has an amd k62 (500) with only 128 mg. ram it is also set up with a dual boot of Win 98 and Win 2000. Tried to take the machine up to 256 mg. ram and get repeated errors from win 2000 unable to boot all the way up in 2000. If I remove the new ram win 2000 boots fine. But I can boot up just fine in Win 98 and 98 also recognizes the new ram. Am I missing a setting change or what in 2000.
I wasnt sure whether to post this here or in hardware issues sorry if im in the wrong place.
Any help on this would greatly appreciated.

 

Set your BIOS back to setup defaults. Does W2K boot OK with only the new stick of RAM installed?
I would try changing the CAS latency setting in the BIOS for your RAM. You will need to search for the recommended latency setting for each stick and experiment if the CAS latency is different for each. This could cause a problem for W2K to boot.
Or maybe simply the two sticks are incompatible under W2K??