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| Click here to select a new forum. | | Powerbase 200 no boot or chime | Posted by: jmayniac on 2024-07-27 10:14:47
I got a Powerbase 200 and it needs some help. The case was in bad condition, but amazingly there is no corrosion or visible issues on the CPU card, logic board and riser board. It was dirty, but otherwise in seemingly good shape. After a thorough cleaning with IPA and waiting a few days to dry, I tried to start it up with it all assembled outside the case. The power light came on, as well as the case and power supply fan, but no chime and no video. I replaced the PRAM battery as I heard they might not chime without that, but still no chime or video. I reseated all the cards and even tried a new known good power supply, but still the same issue. I replaced the RAM, again checking for anything, but no boot.
At this point I've reseated cards and switched any parts I could, but still just the power LED and fans spinning, but nothing else. I even switched out the speaker, but no chime. I've gone over all the boards and don't see any leaking caps or otherwise bad components or traces. The CUDA button seems to do nothing. Removing any boards, including cache does nothing.
Anybody have ideas where I look next? | Posted by: Byrd on 2024-07-27 10:47:14
I’d and place pressure on the CPU card when booting, maybe shift it slightly with each trial. Depending on how these were stored I find the CPU can sag in the slot and cause some issues. L2 cache can also fail but see you have that removed, but keep it out for now. Also try an ATX PSU and check voltages running. | Posted by: jmayniac on 2024-07-27 10:56:45
I did probe around the board on some caps and I see 3.3, 5.08 and 12.3 at various points. The CPU gets hot if I leave it on for a while. I tried some gentle pressure, both up and down on the CPU card and no change. | Posted by: Powerbase on 2024-07-27 12:38:47
Have you tried a known good PCI video card yet? Make sure to seat that PCI riser card good. I know you already do, but still | Posted by: jmayniac on 2024-07-27 13:57:01
Have you tried a known good PCI video card yet? Make sure to seat that PCI riser card good. I know you already do, but still The video chip is on the riser card for the PCI slots. I don't have another that will work on this computer. I have tried both VGA and Mac DB15 connectors though and the same thing. If I take the riser card out and try to boot, there is no change. | Posted by: _AP on 2024-07-31 22:47:02
Maybe try a different CPU if you have or can get one. In my testing, the only time I haven't gotten a chime is with a non-working video card or daughtercard.
Actually, I think I've had no chime when trying different memory, but when I hit the reset button, it would chime and you'd hear broken glass.
Even without PRAM battery I've still had chimes, but no video. I did have an issue with EBL PRAM battery. I used a Saft and had no issues so far. | Posted by: jmayniac on 2024-08-01 07:31:50
Maybe try a different CPU if you have or can get one. In my testing, the only time I haven't gotten a chime is with a non-working video card or daughtercard.
Actually, I think I've had no chime when trying different memory, but when I hit the reset button, it would chime and you'd hear broken glass.
Even without PRAM battery I've still had chimes, but no video. I did have an issue with EBL PRAM battery. I used a Saft and had no issues so far.
I was thinking the same thing, but I don't have another CPU card to try. | Posted by: _AP on 2024-08-01 13:10:51
I might have one but don't know if it works, it's a 180 I think. | Posted by: jmayniac on 2024-08-01 14:55:25
I might have one but don't know if it works, it's a 180 I think. If you do, I would be interested in it. | | 1 |
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