Once more I am reminded of the complicated aspects of the personal computer. Due to the RAM hungry demands of the ever popular MS automatic updates my wife's and my own computer have been slowing down. I knew I needed pc2100 ddr RAM so I went shopping. What was interesting was that I found that density is also important in RAM choice. It appears that high density RAM is considerably less expensive than low density RAM The only defining difference I could find was that low density RAM is 64X8 and high density is either 128x8 or 128x4. What was frustrating was that neither motherboard manual said a darn thing about density on RAM but several articles I found said that high density RAM was only suitable for specific motherboards. I did note that a couple of guys on eBay noted that their RAM was high or low and cautioned that many sellers didn't mention that and no returns for incompatibility. After mixing and match...