Hi, Sounds like "defective" main board. I would suggest getting the main board exchanged under your warranty if applicable. Thanks and have a Great Day! Joe Lore =========================== Hi, Have a pretty new machine with windows XP Pro. Everything is working fine except the keyboard. I can use a USB keyboard but not the PS2 keyboard. I tried a different keyboard on it and still the same no keyboard working. Could anyone here please give me some ideas to try or explore to see if I can fix this. PCBUILD maintains hundreds of useful files for download visit our download web page at: http://freepctech.com/downloads.shtml