Random Reboots

[ahartman]

A couple of days ago, my computer started rebooting randomly. I've done a ton of troubleshooting and can't figure it out.

I built this comp mid-Oct and it's been rock solid until this started happing. Nothing is overclocked.

Rig
Mobo: P35-DS3R (F5 Bio)
CPU: Q6600
PSU: Corsair VX550
RAM: 4GB (4x1GB) Crucial Ballistix
Vid: eVGA 8800GTX
OS: XP Pro (32-bit)

Here's the troubleshooting I've done so far:
1) Swapped out the PSU for a new Antec (same issues)
2) Tested both PSUs with multimeter (12v, 5v and 3.3v all tested fine - boot, idle, load, shutdown)
3) Turned off automatic reboot on error (there's no BSOD with these reboots)
4) Checked the system log (no errors written before/after reboot)
5) Run memtest (reboots happen during this as well, so we can rule out anything with Windows)
6) Run under load to watch temps (never goes about 60C with Prime95)
7) Removed/reseated the HS/Fan (mostly because I was in there messing around, wanted to check the spread of AS5)
8) Full scans for viruses/spyware/adware (nothing found but cookies)

Ideas on where I should look next? I'll double-check the stand-offs, but it would be odd to all of a sudden develop a short, no?

I think my next step is to buy an identical mobo and swap that out to see what happens.

If I booted into the BIOs and left it there, then I get a reboot, then it points to something outside the BIOS/Windows, correct? Something electrical?

Any help would be GREATLY appreciated. I'm absolutely stumped.

 

[Err0r404]

heat issue? do you still have the same problem if you use only 1 or 2 slot of RAM? i have the DS3R and haven't had a major issue.

May be time to RMA the board?

 

[ahartman]

Doesn't seem to be heat related as sometimes it happens within 5 minutes of starting the comp - other times it can happen 3+ hours after starting the comp.

The machine rebooted while in BIOS, so that pretty much rules out anything windows related.

It has to be electric - maybe a short somewhere. Tips on how to track it down?

 

[Old Hippie]

It has to be electric - maybe a short somewhere.

Sure sounds like it. I'd never be lucky enough to find it!

Good Luck!

 

[Slammy1]

You can try a minimum install outside the case to run down shorts, after you've tried a new electrical circuit (which I assume you already have). At the minimum, check to make sure you don't have an extra stand-off anywhere. Just an addition, I know they say not to install them but I'm a big believer in spacers.

 

[hclarkjr]

i notice that you have 4gb of memory on a 32 bit OS. try removing 2gb and see if that fixes the problem

 

[ahartman]

Originally posted by: hclarkjr
i notice that you have 4gb of memory on a 32 bit OS. try removing 2gb and see if that fixes the problem

Thanks for the help, but since the rig had been working fine for 2+ months before this started, I doubt it's related to having 4GB (still haven't ruled out a bad stick though, which I'm working through now, so I'll be able to test your 2GB/4GB theory as a part of that).

 

[ahartman]

I may have found the culprit - something faulty with the reset switch.

I disconnected the lead from the mobo and was able to stay up 3+ hours. I'll run Prime overnight and see how we end up.

Then the decision - RMA the mobo, replace the case, or go without a reset button...

 

[guitarizt]

Just take out the reset btn, I don't even have one.

 

[ahartman]

So I spoke too soon... not the reset button or the lead.

I've done the following:

1) Swap out the PSU - no difference
2) Swap out the mobo - no difference

I've mixed & matched the memory (running 2GB at a time) - memtest will run for as long as the computer will stay running w/o errors as will Prime95.

Last nite, the comp ran Prime95 for 9+ hours. Then later this afternoon, it restarted after 60 minutes.

Heat isn't an issue, under full load, the temps never go above 60C.

The comp will reboot when sitting at the BIOS screen, so it's not windows related.

The only things I haven't ruled out yet:

1) CPU
2) Drives (1 IDE burner, 2 SATA HDs)
3) Vid Card
4) Case

I would think the most likely culprit is the case, so I guess that's the next swap.

Any other suggestions as to next steps?

 

[guitarizt]

I bet it will work if you use a new hd with a new clean os.

 

[andrei3333]

i have the same problem, shuts down every 3 seconds or so and then turns on, all fans and leds work, i was playing with memory timingsévoltage in bios prior to this, cannot reset cmos, tried battery, power plug, jumpers....is it a dead mobo....

 

[jackschmittusa]

Using a UPS? Anything new that may have affected the outlet voltage from the wall?