This evening I was finishing putting together a desktop that I was going to use as a print server among other things. For most part I used spare parts (case, motherboard, CPU, memories, ...) that I had kept from previous upgrades I did of my other computers. Yesterday I finished loading the OS (Win XP Prof) and all the necessary additional software and everything was working just great until I decided to add more memory as I only had 1G. This afternoon I went to TigerDirect to buy 1 more gig of DDR2 memory. I installed it tonight and as soon as I turned the computer on the board went beeping like crazy and I started smelling something burning . I turned it off and checked the new memory module and saw that it was DDR not DDR2. My fault, I knew better and I should have checked it before installing it but I was still infuriated with the TigerDirect guy . Although the pins layout is slightly different between DDR and DDR2 I was able to fit the DDR into the DDR2 slot without forcing and realizing that it was not the right one. Anyway as we say better is the enemy of good, 1G was good enough for what I needed.