Upgraded to Win 10 from XP a few months back and while it's not perfect, it has given me the ability to hook up as many HDD's as my MB can handle, with the option to go to 2TB+ HDD without having to partition them down.
I hated the e-mail function, so I'm using Thunderbird.
As for the OP's graphics problem, I know there has been an update for AMD graphics cards recently...... which I haven't downloaded and installed yet, so maybe that is why my graphics haven't gone pear shaped.
To get totally back on topic, check your graphics settings, maybe something was changed by accident, failing that, maybe your graphics card is getting past it's 'use by' or may just need a bit of dusting to stop it from heating up too much.