On Mon, 2006-01-16 at 12:38, Craig White wrote: > On Mon, 2006-01-16 at 12:35 -0700, Vaughn Treude wrote: > > Hello everyone: > > I've been experiencing a problem with one of my PC's. Eight months ago > > I upgraded it to an Abit VIA KM400A motherboard with an AMD processor > > and new RAM. In the last couple of weeks it's started shutting itself > > off sporadically, for no apparent or consistent reason. I know it's not > > a software problem (though if anyone wonders, I've got Ubuntu on it, and > > have been quite happy with that flavor of Linux) because it has at times > > shut itself off while I'm in the BIOS setup screen. I have replaced the > > power supply and that didn't help. I suppose it's probably a > > motherboard problem, and I believe it's still under warranty, BUT > > sending it back will be a hassle and I'll lose the use of that machine > > for a few weeks at least. Most odiously, I'll have to reinstall the > > processor and mess with that heat sink junk once again. So I'm wondering > > if anybody knows of anything else that could cause this problem. > > > > Some more info: > > - The problem appears to be totally random, sometimes happening within a > > minute of startup, sometimes hours later. > > - Sometimes the system will not restart for a few minutes after this > > happens. Or sometimes it will start but not boot. > > - Often when this happens the BIOS checksum gets corrupted and I have to > > re-enter my settings. > > - In BIOS, I've taken care to turn off features I'm not using, such as > > APIC and SATA support. I've turned off power management to the extent > > the BIOS allowed me to do that. I've also set the power-off switch mode > > to a 4 second delay, in case there could be noise spikes on the power > > switch line. I've turned off the "halt on errors" feature. > > - In the BIOS PC health screen the CPU temperature appears to be well > > within the good range. However, I've only checked this shortly after > > power-on. > > - The motherboard is rather compact, and is mounted in a maxi-tower case > > with extra fans. I don't know for a fact if the airflow is optimal. > > - I've checked the system logs and there is absolutely no record of any > > kind of error at the time it powers itself off. > > > > Any ideas of what I might try, or any resources I could use? I googled > > for it under "PC sporadic shut off" but didn't get any useful hits. > > Half of the problem with googling for a PC problem is knowing what to > > call it! > > > > Thanks in advance for any suggestions you might have, > ---- > I have had that happen from 3 different causes that I can recall. > > The first was a failing power supply which apparently you have already > replaced. > > The second was with a bad cpu fan where the temperature of the cpu would > cause it to shut down. You should be able to monitor the temperatures > but acpi would have to be turned on and with Linux, you would probably > have to install and configure lmsensors and probably something like > gkrellm. > > The third was most recently when a Dell system had capacitors that were > leaking - you could see the gook on the top of the capacitors when you > looked at the motherboard. This is most likely the issue and I would > recommend that you look carefully at the capacitors on the motherboard > and if there is anything other than dust on the top of some of them, > replace the motherboard as there is no other option. > > Also - as a method of control, if the computer is plugged in to a wall > outlet, I would plug a plug strip into the wall outlet and plug the > computer into the strip along with something else that would turn off > (but not back on) if for some reason the power dropped momentarily. > > Craig > Thanks for the ideas, Craig, Miles, Austin, and Cat. I think the CPU fan is OK, and the CPU temperature was good at least when I first powered it up. Unless the fan is randomly stalling out, I doubt it's heat related, since the timing is so sporadic. (Then again, the fact that it sometimes won't come up for a couple of minutes does make it seem heat-related.) So far it's been up and running for 2 hrs now. The next time it shuts itself off I'll open it again and look at the caps. I didn't notice any capacitor gook when I had it open earlier but I wasn't looking for that either. :-) If all else fails, I'll send it back for warranty service. Vaughn > --------------------------------------------------- > PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us > To subscribe, unsubscribe, or to change you mail settings: > http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss > > --------------------------------------------------- PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us To subscribe, unsubscribe, or to change you mail settings: http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss