Windows 7 freezing with the hard drive led on, for a variable amount of time, often until a hard reset is performed, is now a pretty notorious issue with Windows 7 on certain hardware configurations, one of which is the Dell Studio 1735.
My Studio used to suddenly (and randomly) freeze, while the hard disk activity led remained fully on, and I usually had to perform a hard reset in order to get it to work again, only to have the issue reoccur.
I had had a Samsung SSD installed instead of the factory magnetic drive, which I moved to bay number two, and installed Windows 7 Ultimate 64-bit at the same time, and ever since these upgrades I continued experiencing that really annoying “hard drive led on freeze” problem.
I tried many solutions I found online, for months on end, to no avail. I finally found the one that worked, and it’s a very simple and easy to implement solution.
Simply paste the following lines into a new, blank text file, exactly as they are:
Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor\Parameters\Port0] "LPM"=dword:00000000 "LPMDSTATE"=dword:00000000 "DIPM"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor\Parameters\Port1] "LPM"=dword:00000000 "LPMDSTATE"=dword:00000000 "DIPM"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor\Parameters\Port2] "LPM"=dword:00000000 "LPMDSTATE"=dword:00000000 "DIPM"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor\Parameters\Port3] "LPM"=dword:00000000 "LPMDSTATE"=dword:00000000 "DIPM"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor\Parameters\Port4] "LPM"=dword:00000000 "LPMDSTATE"=dword:00000000 "DIPM"=dword:00000000 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor\Parameters\Port5] "LPM"=dword:00000000 "LPMDSTATE"=dword:00000000 "DIPM"=dword:00000000
Save the file, rename it so that it has a .reg extension, than double click it (this will attempt to merge the information from this file with the Windows registry) and confirm your action in the ensuing confirmation prompt.
That’s it. I had no other pesky laptop freezes or hangs since!
The long version of this solution can be found on the Crucial forum, and it relates to problems with the LPM feature of the Intel RST implementation (pertaining to the Intel RAID) interacting with the hard drive (in that case, a Crucial SSD, in my case probably the Samsung SSD, but I can’t rule out the other drive being to blame).
What the above working solution does, is disable the LPM feature via the Windows registry, which seems to take care of the problem permanently. More information on this issue is provided by Intel (since the age of Windows Vista).
This will hopefully work for you, too, even on a different hardware configuration, as long as you use the Intel RAID (namely the RST features).