Hey I tried linux on my computer and loved it im running ubuntu-gnome3 and everytime i start up a game it crashes within 5 or 10 minutes. I have a bog standard HP Envy desktop with i7 - 4770 a GTX-660 (1.5GB), 16 GB ram and 1 Tb hard drive the motherboard is unknow to me but i can find out if you need it.
This also happened when i ran windows which led me to to completely switch to linux erasing all microsoft windows don't know if it is a problem with the actual graphics card.
What is your power supply and your motherboard? also what kinds of games in your steam library , are they as demanding as Farcry and crisis or are they like Quake,