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I have a client's laptop that, on startup, start churning so badly it becomes completely unresponsive. I can get past the login screen, but after that it essentially freezes. Booting into safe mode is marginally better - I can bring up a taskmgr - and see that CPU and RAM usage are both low. Hardware diagnostics pass fine, and I can boot other OS on the machine. I've scanned the entire hard disk for viruses, with no hits. This has happened to the same machine twice in the last month, and the user has said they didn't install anything (or do anything funny) since the last re-image. I'm hesitant to re-image it without diagnosing the problem first, as I fear it might just come back. Any ideas?

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up vote 3 down vote accepted

Have you ran a disk checking diagnostics of the hard drive. My initial gut feeling is that the drive may be bad. Try using a bootable PC repair kit and run a diagnostics on the drive. Hiren's boot CD has some great utilities all rolled into one for PC repair/diagnostics. Also, if you wish, you can use a USB drive to boot from. I recommend using pendrivelinux to set that up. I actually posted a detailed how-to on how to use pendrivelinux if you need it here

Finally, here is a guide on how to check the health of the drive.

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Indeed the drive was bad, but none of the diagnostic tools I used picked it up. When I swapped the drive to another machine, the error followed the suspect drive. When I cloned the drive's data onto another identical drive, the replacement drive worked fine. – askvictor Sep 12 '10 at 22:54

In the Task Manager, add the I/O columns to the process tab to show how much disk I/O is being used by each process. In the Processes tab, click View > Select Columns, then check the columns for I/O.

Better yet, run the Resource Monitor. Go to the performance tab of the task manager, then click Resource Monitor, or run %windir%\system32\perfmon.exe /res. You could also use Sysinternals Process Explorer to find the process causing all this disk activity.

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Run System File Checker offline


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