Have a friend with an older (~2008) Dell Optiplex 755. Dual core Pentium E2220 CPU, Intel 035 Express chipset (ICH9D0), Radeon HD 2400 video, 2 GB DDR2 RAM, 4 SATA connectors. And a dead hard drive.
This is the second dead hard drive. The original was a SATA 160, which was replaced several months ago with a 2 TB Seagate. In its current iteration, the machine was running Windows 7 pro. It was a clean install, and had run quite smoothly.
The 2 TB drive has seemingly quit working. The machine would start to boot and then blue screen and start over. Various diagnostics said the drive was either bad or missing entirely.
I installed a used (smaller) drive in the machine for test purposes. The drive shows up in the BIOS (as does the Seagate), but no Windows install program from XP Pro SP3 thru Win 7 pro will recognize there is even a drive there. UBCD4Win booted from the DVD does not detect it, either. I'm certain the drive is good. I even tried formatting it in another machine and then putting it back in the Optiplex. I have tried connecting the drive to different SATA connectors (which I turned on in the BIOS) to no avail. The SATA DVD is recognized and the machine will boot from it.
When plugged into a Windows 7 machine via USB, I can see both partitions on the Seagate ("System Reserved" and "Local Disk"). I can see the contents of the System Reserved partition, but attempting to view the Local Disk partition locks up Windows Explorer. My previous experience with connecting it directly to an XP machine was that it kept the machine from booting, but connecting it via USB after the machine was booted would let me see the drive and its partitions, but not their contents.
At this point, I'm less concerned about the existing drive than I am about the inability of the Optiplex to see any drive.
I've looked at all the BIOS settings and they seem to be set the way they should. Indeed, the BIOS recognizes the hard drives connected to the machine.
I've run out of things to try. I need some new ideas. TIA.