I had a 1G 3 year old Patriot memory card in my machine, and tried adding 2\nmore identical PC2100 Patriot 1G cards. Things did not go well, so I pulled\nthem out. My first attempt found XP Pro firing up very, very slowly. I\npulled the 2 new mem cards and tried just adding one. That worked for\nawhile, then I would get a blue screen, and have to reboot. I continued to\ntry various combos of the two new mem cards, but couldn't get it to work. I\ncould see the PC knew they were there by looking at BIOS. They are now\npulled, and I'm back to just 1G. Comments?