TehGuy wrote on 2021-09-10, 19:43:Still waiting on the multimeter to test continuity with, but here's the rather disappointing readout on the diagnostic card I go […]
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Still waiting on the multimeter to test continuity with, but here's the rather disappointing readout on the diagnostic card I got
The lights are, from left to right
-12v -- CLK
+12v -- IRDY
+5v -- FRAME
+3.3v -- RESET
LED display shows nothing but dashes
also I think I might've had it plugged in the slot that has that scuffing behind it, if that becomes pertinent.
This tester is not very efficient, I suggest you get one with LCD display like this
But anyway, replace all the capacitors you can, even if they are undamaged, they don't have a very long lifespan, I've already caught problems where the capacitor was visually perfect, but it had a very high latency and capacitance. Also, it's not too much work, once you've changed 2 or 3, you'll have practice, and you'll get the job done quickly.
After that, you can buy an eeprom programmer, and try to record the bios, as it was reasonably common for bios from that era to corrupt at all.
Some tips:
Remove the cmos battery, wait a few hours, then wash the motherboard thoroughly using mild detergent and a toothbrush or brush, let it dry well for about 3 days, I've saved many boards this way, and don't worry, wash it's totally safe as long as it doesn't have energy and it dries well.
Use a dryer to heat the chipset, although this is unusual in the pentium 2 era, some motherboards may have lost ball contact due to improper handling or storage.
Use a contact cleaner spray (not wd40, contact cleaner is that spray that freezes things), you can also use a lighter fluid spray, on the DIP switches, sometimes I had boards that didn't work because they weren't making contact through the inside the DIP, turning them on and off several times each can also help.
With a multimeter, look for voltages of 3.3v, 5v, and 12v on the motherboard, 3V can be found for example in the cmos battery socket, 5v can be found on some coils, and 12v can be found next to the atx connector. If you don't find these voltages, you may be having an electrical problem with the board's power distribution.
Disassemble the processor (removing the heatsink), turn on the board and place your hand on the core of the processor, see if it is heating up, if it is, it is a good sign, if not, it means that the board is not providing power to the processor (probably because one of the voltages mentioned in the paragraph above is missing).
If the processor gets hot, turn on the motherboard without memory, but with the speaker connected (the one that connects to F_Panel), it should emit beeps alerting the lack of memory, if you do, you probably have a problem in the memory slot, heat can help you. If you don't hear beeps, your motherboard may have corrupted bios, or some voltage is missing.