A friend's PC conked out recently, he tells me he'd been getting "incorrect frequency" messages. So he turned it off, and when he turned it on later he got another and soon after it died; no noise or lights when switched on.
Well, I instantly suspected the PSU, but some hours later (after trying a few PSUs) I came to the conclusion that the PSU was fine.
It looks to be either the CPU or Mobo or both, but I'd like to know how I can find out which it is.
Here are my results:
-Oldish P4, socket 478, D845WN mobo
-When everything connected as normal, nothing except a tiny LED next to the 20-pin connected labelled "power". This is on all the time that the PSU is connected to mains. Pushing the power button has no effect.
-I discovered that on removing the 4-pin connector from the mobo (the "P4" cable) and reconnected the PSU to mains, the fans would start, and the HDD light would go solid. This would only happen, however, if the CPU was in the socket, otherwise it would do nothing (but the LED would again be on). Front power button would not turn it off. The CPU and every other chip seemed cold, except for one labelled "American Megatrends" (which I presume is the BIOS) which was just slightly warm after a few minutes of running like this.
-Above behaviour was consistent no matter what else was connected. I took out all the RAM, PCI cards and peripherals and the behaviour remained. No beeps, ever, (and definitely no video output), although it does have a mobo speaker.
-Also tried 1 of the 2 RAM sticks at a time. Nothing new.
-Mobo battery seems fine.
-No obvious damaged components
-I took apart the original PSU and found that the fuse had been removed and bridged with a wire. Perhaps this caused a problem during a power surge or some such...
The fact that there was at one point a difference between processor in and processor out to me hints that the processor isn't a complete potato.
Any ideas on which component it might be, or maybe what else I could try? (I have a meter, but I don't have another socket 478 mobo or CPU - actually I have one Pentium 4, and I don't know what kind of socket it has because I can't remove the heatsink from the CPU (and I don't feel secure about pulling rather hard...))
Thanks,
Mikrondel
Well, I instantly suspected the PSU, but some hours later (after trying a few PSUs) I came to the conclusion that the PSU was fine.
It looks to be either the CPU or Mobo or both, but I'd like to know how I can find out which it is.
Here are my results:
-Oldish P4, socket 478, D845WN mobo
-When everything connected as normal, nothing except a tiny LED next to the 20-pin connected labelled "power". This is on all the time that the PSU is connected to mains. Pushing the power button has no effect.
-I discovered that on removing the 4-pin connector from the mobo (the "P4" cable) and reconnected the PSU to mains, the fans would start, and the HDD light would go solid. This would only happen, however, if the CPU was in the socket, otherwise it would do nothing (but the LED would again be on). Front power button would not turn it off. The CPU and every other chip seemed cold, except for one labelled "American Megatrends" (which I presume is the BIOS) which was just slightly warm after a few minutes of running like this.
-Above behaviour was consistent no matter what else was connected. I took out all the RAM, PCI cards and peripherals and the behaviour remained. No beeps, ever, (and definitely no video output), although it does have a mobo speaker.
-Also tried 1 of the 2 RAM sticks at a time. Nothing new.
-Mobo battery seems fine.
-No obvious damaged components
-I took apart the original PSU and found that the fuse had been removed and bridged with a wire. Perhaps this caused a problem during a power surge or some such...
The fact that there was at one point a difference between processor in and processor out to me hints that the processor isn't a complete potato.
Any ideas on which component it might be, or maybe what else I could try? (I have a meter, but I don't have another socket 478 mobo or CPU - actually I have one Pentium 4, and I don't know what kind of socket it has because I can't remove the heatsink from the CPU (and I don't feel secure about pulling rather hard...))
Thanks,
Mikrondel