Probably the webcam (the driver is from 2006 - PFC027.SYS Mon Dec 04 22:34:41 2006 (4574E8D1)

Please run Driver Verifier according to these instructions:
Using Driver Verifier is an iffy proposition. Most times it'll crash and it'll tell you what the driver is. But sometimes it'll crash and won't tell you the driver. Other times it'll crash before you can log in to Windows. If you can't get to Safe Mode, then you'll have to resort to offline editing of the registry to disable Driver Verifier.

So, I'd suggest that you first backup your stuff and then make sure you've got access to another computer so you can contact us if problems arise. Then make a System Restore point (so you can restore the system using the Vista/Win7 Startup Repair feature).

Then, here's the procedure:
- Go to Start and type in "verifier" (without the quotes) and press Enter
- Select "Create custom settings (for code developers)" and click "Next"
- Select "Select individual settings from a full list" and click "Next"
- Select everything EXCEPT FOR "Low Resource Simulation" and click "Next"
NOTE: You can use Low Resource Simulation if you'd like. From my limited experimentation it makes the BSOD's come faster.
- Select "Select driver names from a list" and click "Next"
Then select all drivers NOT provided by Microsoft and click "Next" (NOTE: just select PFC027.sys if you just want to test that one driver)
- Select "Finish" on the next page.

BSOD BUGCHECK SUMMARY
Code:

Built by: 7600.16617.x86fre.win7_gdr.100618-1621
Debug session time: Mon Sep 27 00:29:24.191 2010 (UTC - 4:00)
System Uptime: 0 days 0:17:59.800
Probably caused by : NETIO.SYS ( NETIO!NsiEnumerateObjectsAllParametersEx+187 )
DEFAULT_BUCKET_ID:  VISTA_DRIVER_FAULT
BUGCHECK_STR:  0xA
PROCESS_NAME:  svchost.exe
Bugcheck code 0000000A
Arguments 80008084 00000002 00000001 830b45ca
ииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииии``
Built by: 7600.16617.x86fre.win7_gdr.100618-1621
Debug session time: Mon Sep 27 00:10:47.722 2010 (UTC - 4:00)
System Uptime: 0 days 0:17:45.332
Probably caused by : afd.sys ( afd!AfdAllocateBuffer+18 )
BUGCHECK_STR:  0xC5_2
DEFAULT_BUCKET_ID:  VISTA_DRIVER_FAULT
PROCESS_NAME:  System
Bugcheck code 000000C5
Arguments 00808004 00000002 00000001 83128067
ииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииииии``
Reboot the system and wait for it to crash to the Blue Screen. Continue to use your system normally, and if you know what causes the crash, do that repeatedly. The objective here is to get the system to crash because Driver Verifier is stressing the drivers out. If it doesn't crash for you, then let it run for at least 36 hours of continuous operation (an estimate on my part).

Reboot into Windows (after the crash) and turn off Driver Verifier by going back in and selecting "Delete existing settings" on the first page, then locate and zip up the memory dump file and upload it with your next post.

If you can't get into Windows because it crashes too soon, try it in Safe Mode.
If you can't get into Safe Mode, try using System Restore from your installation DVD to set the system back to the previous restore point that you created.

If that doesn't work, post back and we'll have to see about fixing the registry entry off-line:
Code:
Delete these registry keys (works in XP, Vista, Win7):
        HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\VerifyDrivers
        HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\VerifyDriverLevel
More info on this at this link: Using Driver Verifier to identify issues with Windows drivers for advanced users