All new memory - but poor performance

I have a HP 6640c pavillion- it came with 64 MB RAM- I ran my programs OK- with mediocre performance. I recently bought 3 128 Mb chips- the day I installed the new RAM - my computer has not been the same. performance is the same and seems even worse than when i had just the 64MB in it. the original chip was pc100 - alll the new chips are PC 100 - what could the problem be? SOmetimes the pc doesnt even want to start up - my gaming is worse than when I just had the one chip in --WHATS UP?

 

There could be a couple of different causes. It could be bad ram, or you may be exceeding what your motherboard can handle. Find out the max ram your mobo can handle. If you are within your limits, I suggest removing all but one stick, rebooting, then checking performance, and working from there. Good luck.

 

Here is info on your memory type.

http://www.crucial.com/store/listparts.asp?model=Pavilion+6640C&x=9&y=18

Have you done a scan and defag?