Frist the details:
Machine: IBM NetVista personal computer 2257-B4U
Config: Intel Pentium III 1.0GHz (256Kb), 128MB, 40GB IDE HDD, PCI Microtower (3x4), Intel 810e, 12x CD-RW, 56K modem, Windows Me (Original), Windows XP Pro (now).
The story starts when this machine had the original XP Home upgrade (from Win ME), but never had any SPs or security patches installed, therefore had a large number of Malware. While cleaning this machine, it became clear that we'll be better off to do a clean install. We upgraded the machine with two 256M SIMMs and installed Win XP Pro. All is well with the install and all updates and patches installed (SP2).
Three weeks later, the machine crashed with a memory error, it turned out to be one of the 256M simms is bad, I swapped it out and cleared the memory error, at the same time, I upgraded the BIOS to the latest version for this machine. When the machine booted into XP, during the startup screen (the one with the Windows XP log and the horziontal running bar), the machine rebooted itself (to POST). The keeps going in circle, however, sometime it just hangs when the XP startup screen appears.
I have done everything possible, reformatted the HD, zero out all the sectors, tried a new HD, cleared the BIOS, swapped out all the RAM with known good ones, put multiple partition on and installed multiple XP systems on each partition, here's the funny part, the same problem happens at the same spot on each partition boot up. I even installed Win 2K on one of the partitions and the same problem during boot up.
I should add that these systems never finished their install process since the system hangs (reboots) during the install process (after the first install reboot).
I unplugged the devices one by one and rebooted everytime, but could not find the root of this problem.
Any suggestions, help, would be greatly appreciated.