Do you have an older LiveCD you could boot to verify that the recent behaviors are software regressions? Given that you're noticing some relation to heat, I'm starting to wonder if it might be hardware death throws? I recently had an R5xx card go out on me due to heat issues (the fan on the card died), and that led to some pretty bad bugs. Swapped out the card with an R6xx one and the things been going strong since.
I gather your system is a laptop though, so video cards swaps might not be in the cards so to speak...
Do you have an older LiveCD you could boot to verify that the recent behaviors are software regressions? Given that you're noticing some relation to heat, I'm starting to wonder if it might be hardware death throws? I recently had an R5xx card go out on me due to heat issues (the fan on the card died), and that led to some pretty bad bugs. Swapped out the card with an R6xx one and the things been going strong since.
I gather your system is a laptop though, so video cards swaps might not be in the cards so to speak...