Hi, I blew this cap by touching the heatsink while I was running the machine with no case. Apparently, suddenly changing from ungrounded to grounded while running a cpu can cause ESD. Who knew? The funny thing is I was had it open to investigate why it wouldn't boot, but all it needed was a CMOS battery, so when it started booting I got worried and held my hand "near" it to make sure it wasn't hot enough to melt the table it was on. I bumped it and: "pop", ozone smell, no more booting, lesson learned, I hope. It would be nice to get this running, as with some very cheap upgrades (pentium D to C2D possibly) it could be my best computer.
The SMD that I could see visibly crumbling seems to be a decoupling cap on the 12v power to the CPU. It was cracking, and had already flaked off a bit, just poking at it a little with a wire scratched it to the state in the picture.
I have had trouble finding a schematic for this board (cap is PC82 on board model PWA J8885 rev A-01, also marked as E187242 F2, or model Connolly from a dimension 5150, also possibly 0HJ054 but that's not printed on the board). A few months ago I though I found a couple different datasheets that might have been applicable but they didn't list the same capacitance; I think they were something like 1 and 4.7 microF (maybe I'll find and link them by the time I finish this post).
Does the capacitance need to be an exact replacement if it's just for power supply decoupling? I was thinking, assuming the decoupler is like a high-pass filter, as long as it's lower in uF than what it's replacing and still fairly close it would be OK. Is that wrong? Can you help me determine the exact value it's supposed to be?
Thanks a ton for any help you can give me.
The SMD that I could see visibly crumbling seems to be a decoupling cap on the 12v power to the CPU. It was cracking, and had already flaked off a bit, just poking at it a little with a wire scratched it to the state in the picture.
I have had trouble finding a schematic for this board (cap is PC82 on board model PWA J8885 rev A-01, also marked as E187242 F2, or model Connolly from a dimension 5150, also possibly 0HJ054 but that's not printed on the board). A few months ago I though I found a couple different datasheets that might have been applicable but they didn't list the same capacitance; I think they were something like 1 and 4.7 microF (maybe I'll find and link them by the time I finish this post).
Does the capacitance need to be an exact replacement if it's just for power supply decoupling? I was thinking, assuming the decoupler is like a high-pass filter, as long as it's lower in uF than what it's replacing and still fairly close it would be OK. Is that wrong? Can you help me determine the exact value it's supposed to be?
Thanks a ton for any help you can give me.
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