Hi I am having this problem with a hard drive no matter if I connect it one machine or the other. Both machines have via chipsets and the drive used to be able to boot from either machine. It shows the bar graph on the white windows screen, then just after that bar graph gets to 100%, just when it would normally bring up the desktop, it reboots. There is a 0.1 second flash of a bsod that starts with "STOP", but I cannot get it to pause at that point to read the full message. Same thing happens when trying to boot in safe mode. When I try to do a repair install it says "no windows installation found". I have run fixboot and fixmbr from the recovery console. I have run thorough scandisk and maxtor powermax - both say the drive is fine. If I boot from a different drive and hook this drive up as secondary, it is fully viewable and appears to be fine. Partition table and file system checker programs say everything is fine. When I enable boot logging, no log file is created. I have not changed any hardware for months. I've had machines fail right at this before and found out it was a corrupted driver, which is why I hoped that moving it to the second machine might allow it to work (other than the similar motherboard most of the hardware is different), but no dice. I have backup up all data on the drive however there are so many programs that I've loaded, I'd really like to avoid an OS relaod. All input is welcome

First question
ATA, SATA, IDE or SCSI? IDE right?
Sounds real dumb i know but is this hardware on the HCL? Make sure it is. Set the pins for primary master? I think i would do the os reload and use it as a slave, but i do understand, you want to understand, right? Oh yes, you set the pins on the other drive as prumary slsve?
Hope this helps

Check event viewer if you see any error message. If it is software related, try doing windows repair.

this was due to a corrupt c:\winnt\system32\config\software file. I restored its backup and all is well