I'm running a 64-bit Mint 15 on a Lenovo x121e with AMD E-450 and Radeon HD graphics. I'm worried about the high temperatures (I had Ubuntu before and never even noticed anything, so I never checked ...
I have a Lenovo Thinkpad T420 with Linux Mint 12 and gnome-shell on it. Its a Intel HD 3000 Graphics card in there. When I'm at home, I have another Screen plugged in (19" 4:3) and everything works ...