However, yesterday my computer shut itself down after about one hour of use, twice, showing a blue screen indicating a physical memory dump with some reference to win32K.sys.
I asked for advice, and was given all sort of suggestions, the most useful, that it hard to diagnose.
But, I am pretty sure that I had an e-reader, a Slick, hooked up via USB connections, both times. I did not connect it, today, and had no crash, after the computer has been on for five hours.
I checked the computer for drive errors, and cleaned up the Registry, using System Mechanic. The computer seems to work fine. Could some hardware connected via USB cause such havoc?