RAM upgrade and overheating issue

I have 8GB of RAM, which is the maximum listed by Toshiba for my laptop, but my CPU as stated here can support 32GB of RAM, is it safe to make that upgrade? at least up to 16GB?

The second question is, my laptop wasn't turned on for over 10 months, now that I started using it, it heats up to the point of shutting down when playing games, which it didn't do before the 10 months break, I changed the thermal paste, still no improvement, could it be a malfunction in the processor itself? what can I do?