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Alright, so I'm going to cover as much of this as I can, but I'm sure there will be more questions, so I'll update this as I get them.

First, the problem: My computer crashes when it 'goes to sleep', though it never enters sleep mode, I just have it set to turn the monitor off after 2 hours. It has been happening for months, but it used to be I could go a few weeks without it happening. Now, it is every single time it turns the monitor off. The most recent change, which I believe accelerated the issue is a driver update to my ATI Radeon Sapphire 4850 HD video card. The card itself already runs hot (I have to keep the fan at 80% most of the time to keep it under 80c idle) but in vista it never really had any issue.

Now, when I say it crashes, I know that's not very specific. So I'll give you the more common scenario that I saw, and then I'll talk about what's changed. When I get back to my computer, and move the mouse or hit a button, my monitor comes back to life, and I see my wallpaper. I can move my mouse around and all of that, but when I move my mouse to get to the start menu (which I have hidden), it does not appear. After a few seconds, my mouse freezes, and my computer becomes inoperable. Either I hold the power button to turn it off, or I wait, the screen turns black, and then it shuts down all on its own (my guess is overheating or something, because my cpu fan starts going full blast). Recently, my screen just displays vertical gray bars and then my computer restarts. Just used the tool found here to find that my recent crashes are blue screens that are due to windows 7. An unrelated issue.

What I've tried: I've rolled back my drivers, and tried newer and older ones. I've checked my BIOS and power saving settings, and I've download a lot of software to try and monitor my cpu usage (which, no, I don't run all the time, and in fact most of it isn't installed anymore).

I've changed my settings at this point so that my computer basically never does anything to limit its power. My next step is just to upgrade my video card, but in the interim, I'd like to be able to leave my computer for more than an hour at a time. I also don't know when I'll be getting a video card, and I would like to figure out why this is happening, so any help at figure out the real root cause and a solution would be greatly appreciated.

Here's all the specs I could think of including for my rig. If I leave anything out that you feel might be relevant, just let me know.

  • Windows 7 Ultimate 64bit
  • Sapphire ATI Radeon 4850 HD - Driver version 8.762.0.0 8/3/2010
  • Intel Core 2 Duo E8400 3.00GHz
  • ASUS P5QC LGA 775 Intel P45 ATX Intel Motherboard
  • 8.00 GB RAM (OCZ Reapers, 4x2GB DDR2)
  • Microsoft MN-730 Wireless Adapter
  • 4TB Seagate Barracuda (2x1TB and 1x2TB)
  • No Sound Card
  • Corsair vx 450w Power Supply
share|improve this question
What's your power supply? Have you checked your ram? – Daniel A. White Sep 14 '10 at 2:02
I did a memcheck when this issue first started happening and got no issues, but I haven't run one in a while. And I'll update the original post, but I have a Corsaid vx450w power supply in the system. – Ktash Sep 14 '10 at 3:24
What is the specific error causing the bluescreen? It is possible that it's related to this problem; for example, if you are getting BSODs from bad video drivers, that might indicate that you have a larger problem with your video drivers which could be causing this as well. – nhinkle Sep 14 '10 at 3:42
The issue from the blue screen is from the NT Kernal. Its ntoskrnl.exe version 6.1.7600.16617 (win7_gdr.100618-1621), with reported address of ntoskrnl.exe+4a587c. No indication of a video card issue in the dump. – Ktash Sep 14 '10 at 4:12
up vote 2 down vote accepted

With the amount of gear in your PC I'd look into the possibility that the power supply is either not powerful enough or is on the way out.

I say this because coming out of sleep is when I would expect your computer will experience the highest immediate load on the power supply, everything is trying to start up at the same time, hard drives spinning up, graphics card initialising immediately into it's high power modes to set up the desktop, and CPU and associated fans spinning up to get the system out of the sleep state. After a cold boot most components spin up after short delays (hard drives) or in lower power modes (CPU & graphics) which means there is less immediate load on the power supply.

If your new higher power graphics card has made the issue worse then that just makes me suspect the power supply more.

Do you have another power supply you can try? Preferably one with a bit more juice?

share|improve this answer
Thorough explaination and that makes sense on being the issue. Something I hadn't considered. Unfortunately I don't have a spare power supply with more juice to test. It will probably be something I need to get when I get a video card. I'll mark this as the answer and post back later the final results once I can switch it out. – Ktash Sep 14 '10 at 15:31
@Ktash Thanks for that. I'm still interested in finding out what exactly is causing the problem as that is exactly the kind of problem that annoys the heck out of me. It could be something like your Wireless adaptor not coming out of sleep properly, have you tried removing that to see if it is causing the crashes? Do you have any other PCI devices? – Mokubai Sep 15 '10 at 8:32
I haven't yet. I'll probably pull it out when I switch out the card. My hope is that one or these, or maybe the combination of them, will fix my issue. – Ktash Sep 15 '10 at 14:27
Just to add a bit more weight to my answer, in the last few days I've had to replace a completely dead power supply (that seemingly tripped the mains circuit breaker when it went) and they said that before the power supply died the computer wasn't going to sleep properly. Replacing the power supply with a decent one brought the computer back to life and also looks like it now comes out of sleep properly. Small world huh? – Mokubai Oct 2 '10 at 20:07
Thought I'd update (been a while I know, but I fixed it). Issue was actually that Ultramon was causing the crash, and not related to everything. But it was a nice excuse to upgrade my system anyway :) – Ktash Oct 14 '11 at 1:16

I would recommend doing the following debugging steps:

  • Disable automatic reboot on bluescreen if you haven't already. You can change this by going to My Computer > System Properties > Advanced System Properties > Advanced Tab > Startup and Recovery and unchecking "automatically restart" under System Failure.

  • If you have access to the Microsoft Diagnostics and Recovery Toolkit (MSDaRT), install it and run the crash analyzer. It will analyze the most recent BSOD dump and inform you of what most likely caused the error.

  • If you don't have access to MSDaRT, you could try WhoCrashed, which purports to do something similar. I haven't used it, but it looks like it might be helpful. It's free for home usage.

  • If your system has any sort of built-in hardware diagnostics, run it. It seems likely that some component of your computer is failing. Running a memory test would be a good place to start, MemTest86 is a good tool for this.

share|improve this answer
Thanks for the info, but I as I ammended in the original post, the BSOD was actually related to a kernel error which hasn't been the symptom in the past. For other crashes, I don't get a blue screen, it just turns off. – Ktash Sep 14 '10 at 15:28

Random crashes are very often connected to CPU overheating.

Some of the symptoms I have personally faced due to CPU overheating are:

  1. Random shutdowns: The shutdowns didn't seem to correlate with anything being done in the computer, or with any device connected or disconnected.

  2. Random causes being identified by the OS: If automatic reboot on blue screen was disabled, the blue screens would blame different things: the graphics card, the memory, and so on. However, those individual devices would have no problem if checked on other computers.

  3. High CPU temperatures: This could be seen through CPU monitoring utilities or the BIOS.

These seem to correlate to a good extent with the symptoms you are facing.

On multiple occasions, I was able to solve the problem by blowing off dust clogging the CPU fan and re-applying thermal paste between the heat sink and the CPU. You should be able to find detailed instructions for your CPU on the Internet.

share|improve this answer
CPU Usage wasn't a very good indication. Unfortunately the tools froze with the rest of the computer. But on reboot, in viewing the temp in the BIOS, it seemed to be running pretty hot. – Ktash Sep 14 '10 at 15:30
Well, I actually meant to talk about "CPU temperature" :). But, from your comment it seems that it could be the actual problem. I've updated my answer with some more details. – Hippo Sep 14 '10 at 16:45

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