First post, by jamesN
I recently got a Compaq Deskpro 466, and it worked fine for a while before it started to have issues powering on from cold boot and then eventually only the lights on the front would light up with no display or speaker beeps. I assumed it was the power supply, which has a proprietary, non-AT power connector for the backplane board. After some research I was able to find the pinout online with one person they were able to get an ATX PSU working with their Prolinea 466 (uses the same PSU). So I tried soldering the connectors onto an old ATX power supply which seemed to work, it turned on and beeped normally. I didn't have a display or keyboard plugged in since I turned it on outside in case it started smoking or caught on fire (this is like my second time soldering anything and I have no clue what I'm doing; yes, I am a dumbass.) Everything was fine for several power cycles over the course of maybe 10 minutes, but I realized the floppy drive wasn't turning on. After some more power cycles it started to have a long, loud beep right after pressing the power button, then a couple short ones instead of a short one or two beeps after several seconds. After this things went back to how they were before; lights on the front come on, no speaker beeps. Power cycled many times to no avail. I unplugged the motherboard, but not the floppy drive and then the floppy drive powered on fine. Then I plugged it back in, floppy drive didn't get powered again. Then I tried plugging in some other things to the power supply, like a couple of hard drives I don't care about. This got one more long beep out of it right after pressing the power button, and that's the last time I got it to make any noise. Additional power cycles had no beeps. At this point I'm split between either something being wrong with the power supply because of the weird behaviour with the floppy drive, or that I killed the motherboard, CPU, whatever. Since that power supply was old and I have no clue when it was last working I tried again with one I know was working fine recently. I'm at the same place I was at before with this one - the floppy drive only powers on when the P1 motherboard connector is unplugged, hard drive power on fine regardless. No beeps, one or two lights on the front are on (it varies, before only one would turn on when it seemingly started normally, now two do). So I'm wondering how this can be that the floppy drive connector seems to only work when one of the motherboard power cables is unplugged. I am fairly certain I have everything wired right, so I don't think that's the problem. I don't know much about electricity, so I'm guessing that's why this seems so random to me. Another thought I have had is that maybe this is some sort of safety mechanism from the power supply, since not all the connectors on the ATX pin are connected to something, only the ones I cut out of it and soldered to the connectors. I'm doubtful about this though, given that it still powers the hard drives.
Anyone care to enlighten me?
Apologies for my extreme naivety.