MegaSack DRAW - This year's winner is user - rgwb
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My computer has just rebooted itself twice after a few minutes use, it's a fairly old system but has been perfectly stable. My guess is that it's likely to be a psu issue but I suppose that it could conceivably be software.
Speedfan doesn't show any obvious issues with voltages or temperatures.
I've had something similiar with dodgy ram. Take out one stick at a time to see if it helps, easy to try.
Mine did it - it was a failing power supply that overheated after being used for a while.
Could be RAM, CPU, power supply, plus many other things....process of elimination...
This ^^.
If it does it after a period of time and then keeps doing it, it's probably heat. Blowing all the dust out and reseating the CPU heat sink ("HSF") with fresh thermal compound is probably as good a starting point as any.
Well I'm confused now, I tweaked a few bios setting and unplugged an old handheld PC and cradle just in case, more out of desperation than anything and then left the machine completely powered down and unplugged for a few hours.
I then thought I'd give it a good workout with SpeedFan (monitoring software) running to keep an eye on voltages and temperatures just in case anything was obvious before a reboot. The thing is the system's been up and running for about 5 hours during which it's been running a full virus scan (with a good cpu load on both cores and the harddrive running constantly, which can pull a fair bit of power and generate a lot of heat). During this time I've also burnt a couple of DVDs (whilst the scan was running) - and the system fails to reboot. It's good of course but I just don't know what was going on this morning or whether it's a portent of coming failure (I've been doing some backup just in case).
Also, the bios power setting for ac power loss is for the system to stay powered down rather than restarting, so if the psu had failed briefly the system shouldn't have rebooted.
Any ideas?
Some virus's also cause repeated rebooting although you've said you'd run a full virus scan.
Also, the bios power setting for ac power loss is for the system to stay powered down rather than restarting, so if the psu had failed briefly the system shouldn't have rebooted.
Scandisk would be a good start, then.
Somewhere in Control Panel -> System Properties -> Startup and Recovery (I think?) there's a setting called "Automatically Reboot" that stops it rebooting if Windows crashes; it'll just blue screen instead, which might tell you something about what's happening.
Phiiiiil, I didn't know that that setting existed, thanks, but it's already unticked so I don't think that the reboot was Windows crashing.
Time was, you could tell whether a reboot was power-related or not by watching whether it goes through the full POST or not. A power blip would cause the PC to do the full memory test etc, where's a 'soft' reboot from a crash wouldn't.
These days I'm not so sure if that's still the case, and a lot of PCs hide the POST under splash screens and the like (though usually you can disable this). Might be worth keeping an eye out next time it does it though.