Hi all,About a month ago my computer restarted for no apparent reason. It was sitting idle, and it just restarted. No BSOD, no warning at all. A couple of days later it happened again while I was searching the web. A month passed and it didn't happen again, so I forgot about it. But last night, it happened again while I was in the forums. I don't know how to diagnose things like that, so any help is much appreciated. I took it to CompUSA this morning, but they were of no help. I then took it to AEM Computer Repair, but they couldn't figure it out either.

Is there anything in the Event Viewer?

Since you're OC'ing, check that temps haven't crept up since you tuned your rig (you did right them down, right?) since with time dust and whatnot aacumulate on your heatsinks, fan blades, fan intake and exhaust grids, etc., reducing airflow and increasing your components' thermal resistance.Cheers,- jahman.

What about power settings? Everything set to high performance? Do you happen to use a battery backup?

Yeah, first thing I would do is to check those temps (CPU, both GPU's and chipset with HWMonitor, CoreTemp, MSI Afterburner...)What volts do you have for 4.5GHz?Isolate things removing GPU's, RAM sticks, sound cards etc...Test the RAM sticks with memtest, 1 stick at a time.Test one GPU at a time with a graphics benchmark/stability toolTest your OC going back to stock clocks and see if the problem persists (although if it stops without OC it couls still be a number of things)Stress test with Prime95, OCCT or Lynx with 1 RAM stick at a time, keep a close eye to temps while you doWhat PSU brand and model is that and how long have you been running it?

I did the Prime95 test a couple of times, but not with each stick of RAM. I'll do that tonight. My temps are CPU @ 23, IOH @ 57, SYS @ 40, GPU1 @ 53, GPU2 @ 54. The IOH temp has gone down since about 7 degrees since I installed the waterblock.I did use Memtest for the RAM, and they all passed. I have added more RAM since then and not tested yet.The PSU is an Ultra 2000 watt, but it was installed after the first two restarts. The first two restarts I had a 1000 watt, but don't recall which brand. As for my voltage, I don't recall exactly, but the system wasn't overclocked the first two times this happened, so it would have been whatever stock voltage is the first two times. I never knew about Event Viewer, so I just checked it out. There is indeed a "critical" event that coincides with each of the three times my system restarted. It says source = "kernal-power", event ID 41, then it gives me a long number. I double checked my records, and that is the only thing in event viewer, and it matches exactly with each of the three times my system restarted.

Well Jeremy, the kernel-power ID41 is the typical error logged in Windows after a sudden shutdown. Unfortunately I don't think that will give us any valuable info about the root of the problem this time.Is it repeatable in some way or totally random?What are your core temperatures like while on Prime95 and for how long did you run it?Do you have another PSU that you could try?try to rule out as many suspects as you can, testing without the GPU if you have onboard graphics, the memory sticks, the PSU is you have a spare one, you could even backup your system and try a fresh naked windows install to see if it's a software related issue. System back ups and Windows installs are pretty fast with SSDs as you surely know. You can test each different drive like that tooOther things you can try: the GPU in different PCIe slots, boot into safe mode to see if it's driver related

It's definitely random. The first time the computer was just idle, the second time I was searching the web, and the third time I was working in GMax.The first two times this happened was with a different PSU, then the third time was with my current PSU. I don't have another to try, but if need be I can get one. I don't recall the temps when I ran Prime95 either time, but I do remember that the IOH went up to 75 during the first 12 hour run, but barely moved at all during the second 10 hour run after I installed the waterblock.As for testing each item individually, I will probably have to wait until I finish building my new rig. It was nearly a month between the last two restarts. I think I will go ahead and reinstall Win7 today if there's any chance that could help. It is indeed notably faster with the SSD.

Ok, it's not the PSU then. Do you run your rig off a UPS or straight from the outlet?Given that it's such a random ocurrence, I would set SpeedFan to log all your temperatures and voltages to a file, so when it happens again you'll have a detailed record of your actual IOH temperature (and core temps, sys temp, GPU temp,...) in the precise moment of the shutdown. Speedfan is free and a nice little tool. Very easy to use also.

Hi Jeremy.I see that you have your overclock working well! How do you like the difference in performance? The restart looks to me like a random power fluctuation, possibly caused by supply variation from the source, not necessarily from your PSU. I have had the same thing happen from time to time when left on 24/7, but very rarely. On the other hand, I have had the power just stop on occassion when under load, as per this thread: http://forum.avsim.net/topic/335232-computer-shuts-down-as-if-power-loss. So far it is unresolved.Kind regards,

...The PSU is an Ultra 2000 watt...

Oh, my! 12V @ 150A !!! :Big Grin: Cheers,- jahman.

Hi all,About a month ago my computer restarted for no apparent reason. It was sitting idle, and it just restarted. No BSOD, no warning at all. A couple of days later it happened again while I was searching the web. A month passed and it didn't happen again, so I forgot about it. But last night, it happened again while I was in the forums. I don't know how to diagnose things like that, so any help is much appreciated. I took it to CompUSA this morning, but they were of no help. I then took it to AEM Computer Repair, but they couldn't figure it out either.

Disable rebooting on error and see if you can get an error message and/or a memory dump. You don't say what OS but try right click on MyComputer - select Properties - Advanced - System recovery - uncheck reboot and check write log.There is a freeware program called Who Crashed - sorry don't have the link - that will analyze the memory dump from above and give you more information.Good luck,Vic

Oh, my! 12V @ 150A !!! :Big Grin: Cheers,- jahman.

LOL yeah, it's insane. I searched the web to see how many rails it has, in case he could try swapping a couple of wires and test the GPU on a different rail and stuff... and then I saw that

Disable rebooting on error and see if you can get an error message and/or a memory dump. You don't say what OS but try right click on MyComputer - select Properties - Advanced - System recovery - uncheck reboot and check write log.There is a freeware program called Who Crashed - sorry don't have the link - that will analyze the memory dump from above and give you more information.Good luck,Vic

I don't think there will be a memory dump of an instant shutdown. Would need to be a BSOD I think. Could be wrong though, definitely worth a look

Ok, it's not the PSU then. Do you run your rig off a UPS or straight from the outlet?Given that it's such a random ocurrence, I would set SpeedFan to log all your temperatures and voltages to a file, so when it happens again you'll have a detailed record of your actual IOH temperature (and core temps, sys temp, GPU temp,...) in the precise moment of the shutdown. Speedfan is free and a nice little tool. Very easy to use also.

I use a UPS. I'll get Speedfan now. I assume this is a good link? I always ask before downloading ever since I got a bad copy of dxtbmp through a phishing site a couple years ago.

Hi Jeremy.I see that you have your overclock working well! How do you like the difference in performance? The restart looks to me like a random power fluctuation, possibly caused by supply variation from the source, not necessarily from your PSU. I have had the same thing happen from time to time when left on 24/7, but very rarely. On the other hand, I have had the power just stop on occassion when under load, as per this thread: http://forum.avsim.n...s-if-power-loss. So far it is unresolved.Kind regards,

I am really impressed with the difference. Going from 3.2 to 4.5 made all the difference in the world for FSX and other resource intensive programs that I use. I had to get to about 3.8 before I noticed enough difference to make it worth overclocking, and then at 4.0 - 4.2 there was no going back, and I finally settled on 4.5 because it was stable and performed better than I had hoped for. I still need to learn about memory, though. I ended up just buying new sticks.