random reboots without BSOD - sometimes several daily

[tgfyhre]

I accidentally posted this in the wrong place yesterday so I'm trying again here.

For around 2 months now my PC has been shutting down unexpectedly and rebooting at random times. Sometimes at idle, sometimes while downloading, sometimes while browsing. Several weeks ago it was bad - it went through several reboots before coming back up. I ran memtest86+ after that, from the CD, and it rebooted twice during the memtest - off the disc - but then memtest ran fine after that. I then made the mistake of scheduling a checkdsk. In the middle of the checkdsk it rebooted again, corrupting something, and Windows would no longer load. I thought I had lost everything. Thankfully I used the Windows 7 32 bit install disk to attempt a repair, which failed at first, but then managed to repair the system by using a restore point.

For a few weeks everything seemed okay after that - no new crashes. Now for the last 2 days I've had several reboots again, just like before. I have no idea what is causing it. I get no BSOD - it just instantly starts to reboot with no warning. I ran WhoCrashed and it said:

Crash dumps are enabled on your computer.
No valid crash dumps have been found on your computer.

One thing I've been noticing in the event viewer is a ton of Microsoft-Windows-SharedAccess_NAT events. The events say:

"The DNS proxy agent was unable to allocate 0 bytes of memory. This may indicate that the system is low on virtual memory, or that the memory manager has encountered an internal error."

I'm including some logs from the SF_Diagnostic_Tool. You'll see lots of the Microsoft-Windows-SharedAccess_NAT errors on the EventSys log I included. I have no idea if this is related but I thought I should mention it. Can anybody please help me try to figure this out? I'm really worried about this. I built my custom Windows 7 PC around 3 years ago and it's been going strong until these reboots started to happen recently. The fact that it rebooted several weeks ago while running memtest86+ off a CD makes me think it can't be Windows related. But I'm stumped. My PC was fine for the last few weeks - now it's rebooting again.

The EventSys log says my last crash was:

The previous system shutdown at 11:02:58 PM on ?4/?17/?2014 was unexpected.

 

[Thedoctor44]

Well there's not that much to go on without dump files but we'll run some hardware tests just to be sure.
Your PC shouldn't never restart whilst running memtest unless it's hardware related.

We can try running Prime95 to stress test your CPU. Please run it for 2 hours.
Follow these instructions.

http://www.sevenforums.com/tutorials/100352-hardware-stress-test-prime95.html

Then can you please run memtest86 again to see if the RAM is failing, you must make sure you run it for at least 8 passes.
Follow these instructions.

http://www.sevenforums.com/tutorials/105647-ram-test-memtest86.html

Post back the results.
From what you described I'm not too sure, well first you say it reboots all the time then a system restore fixes it which makes me believe it's driver or other software related, but then you say it rebooted twice on memtest which makes me believe it's hardware.

I do believe it's hardware, let us know the results.

 

[tgfyhre]

Thank you so much for the response. yeah, I'm very confused. Like you said, since it happened during the memtest it seemed to me I could rule out Windows or software, or drivers even for that matter I guess. But then I've gone for several weeks without issue before it started up again the other day.

Well I'll follow your instructions above, and run both memtest and prime95 according to the links, and I'll post back the results. It might be a day or two since I'll be out for Easter.

I have a battery backup and that never gets triggered by the reboots - I was thinking if it was the power supply failing, wouldn't that trigger the battery backup if it fluctuated or caused any issues? So I thought I could rule out the power supply, but I really don't know. Also, my cpu is overclocked - but I've had the overclock for at least a year and a half and never had issues before. I also ran prime95 when I first dialed in my overclock and there were no problems back then. I overclocked my Intel Core I7 from the base clock speed of 2.67 to 3.5 without any issue. I've even run long video processing jobs for 8-12 hours with the overclocked CPU maxed out at 100%, and never had any shutdowns or reboots before this all started happening.

Also, I keep Core Temp running and it seems to be okay - a bit warm (52 currently) but my apartment is a bit warm currently - when it's cooler the temp drops accordingly. I have lots of fans in the case.

 

[Thedoctor44]

If you get no reboots or anything with the battery backup then it looks like a failing PSU.
How many watts is it?

The problem with hardware testing is it can be expensive because replacement parts are needed and if the part replaced isn't the culprit you've wasted some money.

Unfortunately there isn't really another way.

 

[tgfyhre]

If you get no reboots or anything with the battery backup then it looks like a failing PSU.
How many watts is it?

The problem with hardware testing is it can be expensive because replacement parts are needed and if the part replaced isn't the culprit you've wasted some money.

Unfortunately there isn't really another way.

It's an 800 watt - I bought it when I built my PC around 3 years ago. It has modular connections.

I can't figure it out - when the PC reboots randomly, the APC Powerchute battery backup software never gets triggered, and the battery backup never kicks in when it does a sudden reboot. Accoring to the front display of the battery backup unit, the PC normally doesn't get anywhere close to maxing out the power supply - It usually idles around 280 watts, and only goes up when I really tax my video card with games, which I haven't been doing lately.

I'll try the memtest and Prime95 tests and see how it does. I know what you mean about hardware testing being expensive - and I can't really afford an expense like that right now. This is the first PC I've built and the first time I've had to troubleshoot something like this.

 

[tgfyhre]

Well it crashed again - it shutdown at 6:22:48 this morning. When I got up, there was a black screen saying Windows could not boot. This is what happened about a month ago. It was running fine since my last post here, and then this happened this morning. It gave me the option of inserting my Windows CD and clicking repair, or start Windows normally. I selected start Windows normally, and it booted okay, so now it's running okay for the moment. But I know it will just reboot randomly again. Last month when I got the black screen boot error I had a much harder time booting - I needed to do a repair and system restore. Normally it just randomly reboots - I don't usually get the black screen with the boot error. I really have no idea what is going on lately and I can't keep running like this. Again, no crash dump was created, even though it's enabled.

I noticed again there are tons of SHAREDACCESS_NAT errors in the event viewer. Could this be what is causing this to happen? What is that error anyways? I get tons of these:

"The DNS proxy agent was unable to allocate 0 bytes of memory. This may indicate that the system is low on virtual memory, or that the memory manager has encountered an internal error."

"The ICS_IPV6 failed to configure IPv6 stack."

"The ICS_IPV6 was unable to allocate bytes of memory. This may indicate that the system is low on virtual memory, or that the memory manager has encountered an internal error."

I'll run the memtest and Prime95 tests today on the CPU. Meanwhile here are the latest logs I gathered this morning after the crash.

Could this somehow be an issue with my Virtual memory settings? Again, I don't see how though since it rebooted even during a memtest off the CD a while back.

 

[Thedoctor44]

Right I recommend running some tests.

Please go into the elevated command prompt (Run as administrator) and type in sfc /scannow.

Then can you run a disk check by following these instructions.

http://www.sevenforums.com/tutorials/433-disk-check.html

Lastly can you download and run SeaTools for windows to test your HDD and see if it's failing.
Follow these instructions.

http://www.sevenforums.com/tutorials/313457-seatools-dos-windows-how-use.html

Post back the results.

 

[tgfyhre]

Right I recommend running some tests.

Please go into the elevated command prompt (Run as administrator) and type in sfc /scannow.

Then can you run a disk check by following these instructions.

http://www.sevenforums.com/tutorials/433-disk-check.html

Lastly can you download and run SeaTools for windows to test your HDD and see if it's failing.
Follow these instructions.

http://www.sevenforums.com/tutorials/433-disk-check.html

Post back the results.

I'm afraid to run any disk checks right now - as I posted when I first started the thread, it rebooted once while I was running Windows checkdisc. It corrupted something in the boot configuration and I couldn't go back into Windows. I needed to put my Windows install disc in and do a "repair" option, which still failed. After it booted into the Windows disc again, it offered to do a system restore. That worked and then Windows ran smoothly for several weeks until these reboots started happening again last week. If I didn't have a system restore point back then, I doubt Windows could have recovered. It was looking bad.

So I don't want to take that chance and run another checkdisc with the risk of the system rebooting at any time during the test. I ran checkdisc a few weeks ago after that mess and everything seemed okay. But I didn't do a full sector scan. I'd run Seatools or WD diagnostics but I'm afraid of corrupting the boot section again if I run those tools and it reboots again.

Also - as I posted below - my PC just went through another series of reboots, including one while I was in he bios. So could it be a failing hard drive if my PC reboots while I'm in the bios, or while I'm running memtest like last month? I don't see how?

 

[tgfyhre]

And it did just go into a fit of reboots again. I was at the 1-hour mark of running the Prime95 test when it suddenly rebooted. Up until the reboot it was running fine - everything was passing fine. While it was running I was reading up on overclocking (which as I mentioned earlier I had done long ago on this PC), and I noticed sometimes it's recommended to disable hyperthreading for my Intel Core I7 920 chip when overclocking to reduce temps. During the Prime95 test, the temp for all cores was around 82-83 degrees C which is high but that was during full load.

When the system crashed and rebooted a few minutes ago, I went into my Asus P6T deluxe (V1) bios to disable hyperthreading to see if I could reduce the temps a bit - and before I could even do that, it rebooted again, while I was in the bios! What could cause that? So I went in after another attempt and disabled hyperthreading and rebooted. Now it's running ok as usual, with Hyperthreading disabled. I see 4 cores now instead of 8 with hyperthreading. I have to go out in a bit so I won't be able to run Prime95 again until tonight. But As I mentioned near the top of the page, nothing has changed in my overclock settings, and I used to run video encoders for 10-12 hours without issue, maxing out the CPU at 100%.

Really concerned here. Something is very wrong with my system. If it's the power supply crapping out on me, wouldn't that trigger my APC battery backup to kick in, so my computer wouldn't reboot when the power supply craps out?

Right now I'm testing Prime95 to see how the temps are doing with hyperthreading off for my overclock, and the temp is holding steady at 70 Celsius currently after a half hour with Prime95 running. It was running at 82+ before I disabled hyperthreading. I have to leave soon so I can't let it run much longer for now.

EDIT: well Prime95 has run for an hour now and no crash - but of course it can happen at any time and it crashed after an hour earlier today, so that doesn't mean anything I guess. I have to head out now. I'll try and run it again longer later.

 

[tgfyhre]

If you get no reboots or anything with the battery backup then it looks like a failing PSU.

Can you elaborate on this? I'm trying to understand under what circumstances my battery backup will kick in. Last month I killed the power at my fuse box to test it and the battery backup instantly kicked in flawlessly, and it passes monthly tests fine.

If my power supply is failing, wouldn't the battery backup kick in? The fact that the battery backup doesn't kick in, and the PC is crashing and rebooting, suggests to me that it isn't the power supply. But I don't know.

 

[Thedoctor44]

Well because your PC is rebooting even in the BIOS I still think it's hardware, sorry I posted the disk check link twice (Updated now).
Can you run Prime95 in safe mode, that will help us rule out a software issue.

Well you can try running your laptop on battery and see if it reboots (charge it when you go to sleep or when it's off).

Run SeaTools as requested earlier as I've updated the link.

 

[tgfyhre]

Well because your PC is rebooting even in the BIOS I still think it's hardware, sorry I posted the disk check link twice (Updated now).
Can you run Prime95 in safe mode, that will help us rule out a software issue.

Well you can try running your laptop on battery and see if it reboots (charge it when you go to sleep or when it's off).

Run SeaTools as requested earlier as I've updated the link.

I'll run Prime95 from safe mode. By the way, it's not a laptop. It's a full PC - I built it around 3 years ago - it's the first PC I've built. It's always run fine until this started happening.

Out of curiosity, could it possibly be the hard drive? If it happens even during bios configuration and memtest off a cd, wouldn't that rule out the hard drive? Can I run seatools safely while I'm having this reboot issue? What if it reboots during the scan? As I said earlier, once before I ran a checkdisk on my hard drive and it rebooted mid-way, causing all sorts of boot issues for me. I'm scared to chance it again.

 

[tgfyhre]

Another thought - on another forum, I read that really there's only 3 ways a PC can reboot/shutdown without a bluescreen:

• PSU shuts down
• CPU shuts down
• Motherboard shuts down?

Is this accurate? If so, then I guess this narrows it down quite a bit.

I did have to disconnect my modular power supply connectors briefly many months ago. I'm wondering, when I reconnected them - maybe I accidentally swapped out a couple of the plugs? Some of the modular connectors are unique plugs and some share the same type so they can be swapped from one plug to another. I wonder if somehow I switched connectors when screwing them back in and now I've got too many amps running on a single rail? Last night my PC rebooted just idling, so it's not like it had a heavy load. During the Prime95 test this afternoon my APC battery backup said the load was 467 watts. Currently, just browsing and downloading, it's drawing 315 watts (of course these numbers include my LCD monitor, router, etc, which is all running through my battery backup). With my monitor off the battery backup reads 280 watts currently. That's with 4 hard drives in my PC and a GTX 570 video card. This is my power supply:

XION Supernova XON-800R14N 800W
http://www.performance-pcs.com/catalog/index.php?main_page=product_info&products_id=26182
http://www.newegg.com/Product/Product.aspx?Item=N82E16817190016

I'm leaning more and more towards the power supply being bad. But I really have no experience in PC's other than what I've taught myself. Another note of interest - I read this earlier today on a forum:

"If you need to leave the PC for a few minutes before a reboot will work, this is also a strong indicator of a PSU problem."

I have noticed that often my PC will go into "fits" of multiple reboots in a row, as it did earlier today. It rebooted, and rebooted again while loading the bios, and again while I was in the bios. I notice if I leave it off for a few moments before restarting, especially if it's going through a series of reboots, it seems to be more likely to start up without issues.

 

[Thedoctor44]

I'm afraid hardware testing is one of those things where you have to take a risk and buy the hardware to see if that fixes it.

From what you've described the PSU seems faulty and a replacement looks needed.

 

[tgfyhre]

Well I ran Prime95 today. I ran it for 3 hours straight on the top test option (max cpu, no ram). It ran fine for 3 hours straight with no errors. I then decided to run furmark to see how that would go while Prime95 was still running. It's been about an hour now with both running - 4 hours total for Prime95 and 1 hour with furmark. With both my cpu and video card maxed out, here's what I've got for numbers:

cpu
75-78 celsius (distance to TJ Max - 22-25)
80-82 celsius (distance to TJ Max - 18-20) - these 2 cores run a bit warmer than the other 2 above

Nvidia GTX 570
82-83 celsius, 84%-85% fan speed (max fan speed for this card unless unlocked - card doesn't downclock until it hits 95 degrees)

battery backup reads around 560 watts running through it with monitor switched off. My power supply is 800 watts.

room temp - 74 degrees


I haven''t had a reboot since Friday, when I had that string of them. After the string of reboots on Friday, I disabled hyperthreading in my bios, so I use only the 4 physical cores, but kept my 3.5Gz overclock on my Core I7 920. Since I disabled hyperthreading, my temps have dropped around 10 degrees when maxed out, and I haven't had a single reboot. Of course I've gone for a few weeks without a reboot before and then it started again. And reboots have happened even at idle or using memtest in the past, so it certainly wasn't the temps that caused the reboots. But today everything seems stable with these tests. I'll run memtest+ later. Is it possible by disabling hyperthreading with my overclock I could have increased stability? My pc ran for over a year and a half with hyperthreading enabled with my overclock, but only just started acting up a few months ago.

Still wondering what this means for my power supply.

 

[Thedoctor44]

Remove all overclocking, it can cause high instability.

 

[tgfyhre]

The thing with the overclocking is I've ran it for over a year and a half with this overclock with no issues and no reboots. As mentioned earlier I've run video encoding software with the overclock for 10-12 hours running the cpu at 100% - and never had any reboot issues. Now over the past 3 months I get these random reboots, even at idle or running memtest or even just being in the bios. Could the cpu be less tolerant over time of overclocking?

And could the overclock cause reboots during memtest and being in the bios? As I said, I disabled hyperthreading the other day and it's been good ever since. I hate to lose the overclock because that's why I bought this particular chip in the first place - I even went for a particular stepping to overclock better. It's only overclocked to 3.5 from the stock 2.6, but it seems to make a noticeable improvement in much of my software and gaming.

 

[Thedoctor44]

I will admit I don't know that much about hardware (I need to learn really).

If you want an answer I will request somebody.

If you get anymore issues let me know.

 

[tgfyhre]

That would be helpful if you could. I still need to run my memtest+ again, but I've been really stumped trying to figure out what could be behind this. It does seem to be pointing to hardware, but my cpu/gpu tests yesterday did just fine, and there hasn't been a reboot since Friday, so I'm curious what somebody thinks about this that is familiar with hardware issues.

 

[essenbe]

tgfyhre, I'll try to assist you but first, I need you to do a few things for me. I need you to fill out your system specs for me in as much detail as possible. To see more of what we would like, you can click 'my system specs' at the bottom of this post to see mine. If you click the same thing at the bottom of your last post you will have a link to edit system specs. Fill it out with as much detail as possible including manufacturer, model and size if you can. That will help us to help you and will always be available to us in any post you make. If you need help this will help you http://www.sevenforums.com/tutorials/180324-system-info-see-your-system-specs.html

If you don't already have it, please download and install CPUz, Please post a screenshot (http://www.sevenforums.com/tutorials/9733-screenshots-files-upload-post-seven-forums.html) of the CPU, Mainboard, Memory and SPD tabs. On the SPD tabs you can select each dim slot from a dropdown list in the upper left. I only need the slots that are populated.