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I have Lenovo W500, 8GB RAM, 250GB Crucial SSD running Windows 7 x64 using boot-to-vhd.

Lately I started to experience some random freezes for 5-30 seconds. And when I say "freeze" I mean it; it's like a time machine - no input taken, nothing is written anywhere, no log, no disk activity. And then suddenly machine would wake up and continue as if nothing happened.

I do suspect that it's one of the drivers but I don't see any updates in the log lately except for .NET 4 framework and Adobe Reader. Out of new or updated software I can only recall Skype and IE9 but freezes started to occur definitely before IE install.

Regular software includes but not limited to: Office 2010, VMWare Workstation, IE9, Chrome, Skype, Seesmic/TweeterDeck, Live Writer.

How should I approach the "hunting season" to find our the culprit? Any tools or packages that could help me to identify the component, program, driver that causes the freeze?


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migrated from Feb 21 '11 at 3:58

This question came from our site for system and network administrators.

up vote 4 down vote accepted

How do I capture a trace of the freeze?

Please run the instructions of How do I troubleshoot a Windows 7 freeze or slowness? so we can pinpoint the issue. :-)

What can I see on the graph?

Zooming in on the details and getting the right tabs open results in this clear image.

enter image description here

What do we see?

  • CPU 1 freezes at 489,5, caused by the System process, due to an DPC caused by the purple event.

  • A hard fault caused by the green event, this can happen because CPU 2 is still working.

  • The disk is used like crazy because of the red event, looks like VMWare.

What do we see if we click further?

  • The purle event is Microsoft-Windows-WLAN-AutoConfig// launched by its service.

    As this results in a CPU freeze, your wireless drivers are most likely to be the culprit.

  • The hard fault is just the search indexer running on the CPU 2 because it thinks your PC is idle, ironic.

  • The red event is VMWare reading the VM disk, although it does this for a very long time...

    Nothing special, but as you are already running VMWare before the freeze itself occured it seems that your VMWare might have an influence on your wireless too.

What to do?

  • Try updating your wireless drivers (or disable and use a cable if it's an option).

  • Try to keep an eye on VMWare, perhaps update it to the last version or use alternative VM software.

  • Do not disable WLAN AutoConfig unless your drivers provide replacement software.

I hope you can resolve it this way, it's not the first time I see wireless drivers manage to freeze a laptop.

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As per the link above, I've uploaded trace files (each about 60MB): myTrace and user and kernel traces. The "hanging" occurred right near the end of the trace (and I could not find how to truncate the start portion so apologies for the size). If anyone is willing to take a look and shed some light on the culprit, I would be eternally grateful. – georged Mar 27 '11 at 23:29
@georged: Working on it... – Tom Wijsman Mar 27 '11 at 23:45
@georged: Done. Tell me if anything is unclear or the problem is still there, then another trace might help... – Tom Wijsman Mar 28 '11 at 0:06
@tom-wijsman Wow - speechless. And I always suspected video driver. I most certainly owe you one. Will update/disable wireless and report back. – georged Mar 28 '11 at 2:04
@tom-wijsman Unreserved "thank you". Updated wireless driver to the latest and have not had a single "hang" for two days. Awesome. – georged Mar 30 '11 at 1:28

The first thing to do is check to make sure all your drivers are as up-to-date as possible. Then remove anything not needed for your computer to run from startup. You can use msconfig, but if you want to be able to quickly remove all non-crucial boot items, you can try installing Soluto, which as a bonus will show you the approximate time it will shave off your boot and what each boot item actually does. If this gets rid of your problem, you can add things back into your startup list one at a time. Again, Soluto will help you there by showing community reccomendations.

If you're reluctant to install a new program like Soluto, and find msconfig and manually Googling each item too difficult or tedious, many anti-spyware programs will offer some form of help with tweaking your startup list. If you use Spybot, that has a good tool for this in advanced mode (menubar "Mode" -> "Advanced Mode", then sidebar "Tools" -> "System Startup"). Windows Defender should have an option for this too, but you might pull your hair out trying to figure out how to do it (I've been working with it on and off since it came out, and I still can't understand it).

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