I have an HP Pavilion 7940 1 gig Intel CPU 256 ram 40 gig hd.
At boot up it does post fine, identifies CPU, counts ram, see's all devices HD CD etc, and then goes STRAIGHT to a blinking cursor and after 4 sec a DOS message appears that says "error loading operating system" and hangs there indefinetly. .
I went into Bios change boot order to Atapi CD rom first. I then load a bootable CD, and still same results!
I don't even hear the CD-Rom spin up, though the door will open and accept a bootable CD!
I tried clearing CMOS, but to no avail. The same message appears immediately after POST?
I swapped out a good hard drive that had a working copy of XP and still no luck
Is your good hardrive ide or sata? Be sure your boot order is correct and ide is selected in the bios for your sata drive. And if you are using an ide drive, the jumper must be checked for configuration. I would guess that a sata driver is missing. I use the hardrive software cd to format and make an exact copy of the old drive. This must be done while running windows. The software will detect your drive when windows won't. Also check for a loose cable to either your optical drive or hardrive.
Yeah, double check that jumper, do NOT set it to cable select, if it's the hard drive the OS boots from make sure it is set to Master. Sometimes boards are very picky about that. I think I once fried a board that way, and had a tech tell me he was suprised it booted that way. Also, be sure your drive is one IDE 0, or IDE 1, whichever is the lowest number on your mobo.