EDIT: So I ran across a Japanese site - this one - where someone had posted full pinouts about the PSU... especially how to turn it on. Which I did and it fired up just fine. I plugged in a couple of dead hard drives (to simulate load) and tested each of the power lines. Only oddity I found was that the standby voltage changes very slightly depending whether the PSU is on or off (4.79V when off, 4,87V when on). I highly doubt that the very slight (0.1V to 0.2V) inconsistencies between nominal voltage and what I measured.
Still the thing wouldn't exactly power on, even with my jury-rigged PRAM battery.
I say it wouldn't turn on, but I think it sort of did. I pressed the 'reset' button, then the power switch and a little green LED on the motherboard came on along with the LED on the power switch. The CPU fan didn't spin up however. I let it sit like that for a moment, then tried powering it on again - and nothing. I tried forcing power into the system just to watch some fireworks, but then the speaker popped, the CPU fan came on and the LEDs too... but no chime and I couldn't get a picture regardless what dip combination I used on my adapter.
After forcibly powering it on a few times, now it powers on and it chimes - but still no picture.
What even is going on.
A friend of mine gave this to me, after apparently finding it near a recycling bin. Obvoiusly in completely unknown condition and such... there was even a CD stuck in the drive. Its front had also fallen off and now it looks even uglier than usual.
After a bit of cleanup (all the dust was under the motherboard) I decided to measure the outputs of the PSU and well, I discovered that this thing makes a weird clicking sound. So at this point I'm assuming the PSU is gone. Since it's apparently horribly difficult to find an AT power supply locally, how do I troubleshoot and possibly repair it? If I can't repair it, can I modify an ATX PSU to work with it?
The clock battery is obviously dead but thankfully I can replace it with three AA batteries in parallel. Thankfully the hard drive is working. I could probably test the optical and floppy drives but eh, I've got more pressing problems with that system.
Now there's yet another problem: how do I get video out of it? I can't seem to find an adapter locally and I'm not at all willing to wait weeks for one to arrive from who knows where so I decided I should make my own. Problem is, I can't seem to find the pinout for that Apple display port. I've also got a Matrox Millenium GPU (Matrox Millenium 590-05 REV.B 4MB), which I've read can be used as a passthrough for video... and of course I can't really find the pinout of the port on the card itself (it has VGA and another wider port, I'm talking about the wide port whose name I don't know). The idea here is, obviously, making either the Apple-to-Matrox adapter or the Apple-to-VGA adapter, so I need to foind the socket pinouts.
Still the thing wouldn't exactly power on, even with my jury-rigged PRAM battery.
I say it wouldn't turn on, but I think it sort of did. I pressed the 'reset' button, then the power switch and a little green LED on the motherboard came on along with the LED on the power switch. The CPU fan didn't spin up however. I let it sit like that for a moment, then tried powering it on again - and nothing. I tried forcing power into the system just to watch some fireworks, but then the speaker popped, the CPU fan came on and the LEDs too... but no chime and I couldn't get a picture regardless what dip combination I used on my adapter.
After forcibly powering it on a few times, now it powers on and it chimes - but still no picture.
What even is going on.
A friend of mine gave this to me, after apparently finding it near a recycling bin. Obvoiusly in completely unknown condition and such... there was even a CD stuck in the drive. Its front had also fallen off and now it looks even uglier than usual.
After a bit of cleanup (all the dust was under the motherboard) I decided to measure the outputs of the PSU and well, I discovered that this thing makes a weird clicking sound. So at this point I'm assuming the PSU is gone. Since it's apparently horribly difficult to find an AT power supply locally, how do I troubleshoot and possibly repair it? If I can't repair it, can I modify an ATX PSU to work with it?
The clock battery is obviously dead but thankfully I can replace it with three AA batteries in parallel. Thankfully the hard drive is working. I could probably test the optical and floppy drives but eh, I've got more pressing problems with that system.
Now there's yet another problem: how do I get video out of it? I can't seem to find an adapter locally and I'm not at all willing to wait weeks for one to arrive from who knows where so I decided I should make my own. Problem is, I can't seem to find the pinout for that Apple display port. I've also got a Matrox Millenium GPU (Matrox Millenium 590-05 REV.B 4MB), which I've read can be used as a passthrough for video... and of course I can't really find the pinout of the port on the card itself (it has VGA and another wider port, I'm talking about the wide port whose name I don't know). The idea here is, obviously, making either the Apple-to-Matrox adapter or the Apple-to-VGA adapter, so I need to foind the socket pinouts.
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