If I understand you correctly, there are 2 possibilities: 1. The dimm slot won't take anything bigger than 32mb. or 2. It won't take pc100 (the module I now have is 32mb pc66) I borrowed a 32mb dimm (pc100) and replaced my 32mb (pc66) module with it and something really strange happened: On boot up it showed 32mb which would mean 4x4mb simm + 16mb dimm. So again only half of the dimm module was recognised. I was unable to get a 64mb dimm pc66 to check possibility No.2 but what I don't understand is why there's no error message at all. Surely there would have been an error message if the module speed was wrong? Instead everything booted up as normal except it would recognise everything in the 4 simm slots but only half of the dimm module. I would appreciate more advice. Thanks. Julie _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp Visit our website regularly for FAQs, articles, how-to's, tech tips and much more http://freepctech.com