I posted this in the malware forum recently because I wasn't sure if it was a software or hardware problem. After running some malware tests the problem has continued, so I'm thinking it must be hardware somehow. Hoping somebody can give me some ideas on what exactly might be wrong. Here's the malware thread: http://www.bleepingcomputer.com/forums/t/518226/windows-7-problem-freezes-up-over-several-minutes-not-all-at-once/
Windows 7 Professional SP1 - Dell laptop
For a few days now (over a week now) I've been having problems with my laptop. It will randomly (seemingly) cause several open programs to stop responding. When I sense this is happening, during the first minute or two I can usually switch between open programs and even close some of them and I can ctrl-alt-del and open task manager. Within a minute or two though everything stops responding and I can no longer switch between programs, close programs, ctrl-alt-del, or anything else. The mouse pointer still works, as do the NumLock/CapsLock keys on my keyboard, but everything in Windows is no longer responding. I cannot log off, shut down, etc. Windows never recovers and the only way out is to hold down the power button to kill the power. I've not found any pattern to indicate what will cause this to happen in regards to what programs I do or do not have open. One time it occurred while Windows was in the process of logging me in, but before the desktop appeared.
While this is happening, if I watch the hard drive activity light on the laptop it is primarily off, with a brief flicker every couple of seconds or so. During normal usage the hard drive light is usually on or flashing constantly almost all of the time.
It appears to be hard drive related, given the sudden decrease in HD activity according to the HD indicator light. Yet, I've run a full CHKDSK at restart, including surface scan with no apparent problems. I've run numerous BIOS-based diagnostics, including multiple different HD tests, and all passed successfully. I've run ESET's Online Scanner and it found and cleaned 2 threats (listed below) but the problem still remains. I've run full BIOS-based RAM diagnostics with no errors found.
ESET removed threats:
I used System Restore to roll back my machine to two different restore points prior to when this problem started happening, and that didn't change anything either - which I think points to a hardware problem? Yet all hardware tests have passed.
Any ideas on what is going on?