Haven't bought, but I got some "not working" computer parts. I decided to try repairing them, so I found:
- A server, dual-Slot1 board. This should fit nicely to my Zenith server casing, it's for such mainboard, I got it upgraded with some Sempron.
The first problem was the CPU fan not spinning. I quickly located the faulty transistor which I replaced with typical BC547+resistor. However, the mainboard still didn't start. I found that the BIOS is flashed in half! Someone probably tried to fix the cooling by upgrading the BIOS on unstable mainboard and it overheated in the middle of the procedure.
- An Intel AS mainboard for early Pentium. The problem with video artifacts has been fixed by removing the VRAM chips and cleaning their conections.
- A couple of Abit boards with erased BIOSes by CIH epidemic. After re-programming chips they're OK.
- A nForce2 powered board for Athlon, the then high-end one with SATA, LED display for error code and fast AGP. The problem was definitely in capacitor plague, but I think that the main reason was the error in BIOS upgrading procedure. It looks like someone tried to repair these mainboards by upgrading their BIOSes. Trying to locate someone with FWH/LPC adapter for Willem programmer.
- Another Socket Abit board, this time someone got a Celeron with broken protective layer on the core. This is usually not a big problem if crack is not deep, but someone tried to "fix" it by applying enormous amounts of "silver grease" on the WHOLE chip. Yes, on resistors too. MOSFETs blown (replaced, tested, give proper voltage). Switching transistors blown (replaced, tested, OK). BIOS blown to the degree that it doesn't read one address line in programmer. I'll program another chip only because I'm curious what parts have survived.
- Asrock Pentium 4 HT board. BIOS chip removed, whereabouts unknown. Capacitor plague.
After re-programing BIOS I committed one of these lazy things in repair: It has a data block with network adapter parameters in BIOS, but it's not programmed when upgrading. Because I programmed from empty chip in a programmer, I got 00-00-00-00... MAC address and on-board ethernet turned off. Instead of trying to update the MAC using some hardly accessible software I just hot-swapped the BIOS with the chip programmed with pseudorandom bytes, then displayed the MAC from DOS tool and found the address of bytes I got. After burning a patched BIOS I found the network adapter operating.