Yesterday, I was trying to fix a P4 era IBM desktop.
This one has a P4 3Ghz HT CPU, 768MB RAM (512MB + 256MB upgrade), some AGP video card, 2 hard disks (one SATA and one IDE) and 2 optical drives. The motherboard is some IBM rebranded Intel (Foxconn) board.
The case and PSU are proprietary (but PSU uses a standard ATX plug). PSU is Hipro 230W (?) with a dead fan.

Now the problem:
The title says it all. The system is stone dead. It does nothing except turning on and off. Tried clearing CMOS, running with a different PSU, swapping video cards, running on integrated VGA, running with only one RAM module, running without any RAM at all (no beeps).
This system does not show any signs of life. No beeps and nothing on display. The hardware shutdown (hold power button for a few seconds) works though. I suspect that the BIOS might be corrupt (and there’s no way to restore it because the BIOS chip is soldered in). Too bad I don’t have a POST card…

None of my s478 boards fit in this proprietary IBM case so I cannot just rebuild the PC using one of my s478 boards.
So this system is probably good for parts only (CPU, RAM, VGA, HDDs, etc.) unless the system owner would find a compatible board that would fit.