I have a few problems with my laptop, which is running Windows 7 home premium. Sometimes when I boot up and create a document I notice that the system date has been changed to two years previous. I didn't revert to a backup or anything, I'm not sure why the date changed without any messages or error warnings.
Occasionally my system slows down for no reason, freezing up briefly and taking longer to process things even though there are no background programs running. It does this while working on simple text documents or my bookkeeping software, nothing that would consume an unusual amount of RAM. At the same time, my internet connection slows down or drops out, while my partners connection (same network) is working fine. Disconnecting from the internet, waiting then reconnecting sometimes helps.
I have the current version of Norton 360 which is up to date. Not sure why my system would become unstable while connected to the internet if virus scans are coming up clean.