1999 PC won't boot, no beeps however and green motherboard light

Posted by Odd_Mycologist_9435@reddit | vintagecomputing | View on Reddit | 13 comments

My grandparents old pc I've been trying to fix won't boot. a week ago it said no operating system, now it just wont display period. However, there are no beeps indicating hardware issues and a green light for the mobo LED. I'm stumped, I've tried cmos reset, different gpus, and plugging/unplugging various cables. the monitor and cables are all working. I'm very confused bc it turns on yet has no sign of issues. also, the psu fan doesnt spin, i looked inside it but everything looks ok. I can send pics if u need.
Any help is appreciated (:

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thatguychad@reddit

Try a different power supply. An LED only needs \~3v and low current to light, powering up everything else needs many amps and 3.3, 5, and 12v rails.

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Odd_Mycologist_9435@reddit (OP)

problem #1. the spare psu i have has a 24 pin mobo cable, this pc has a 20 pin

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thatguychad@reddit

If there’s room for the unused 4 pins to hang out next to the connector, that will work. There was a time when power supplies used a 20+4 connector during the transition

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Odd_Mycologist_9435@reddit (OP)

so i get a green led form mobo and psu, however the pc makes one quick sound and then nothing. ive only connecting the motherboard cable bc thts technically all it needs to boot

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thatguychad@reddit

It could still be caps. That’s right around the time of the capacitor plague. Post a picture of the caps around the CPU and memory.

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Odd_Mycologist_9435@reddit (OP)

here you go, pardon my hand moving the cables out of the way

looks all good imo but ur better than i at identifying this

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thatguychad@reddit

Well, the good news is that you don’t appear to have any electrolytic caps on the motherboard itself. You also don’t have a Varta bomb on the board and have a coin cell battery, instead. However, your VRM has several electrolytic caps that should be inspected. The VRM is the module that says “input 5vdc” on it. To remove it, push the two white tabs down and toward your CPU slot while simultaneously pulling straight up on that module. Get a picture of that if you can.

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