Ubuntu 12.10 (and 12.04 earlier)

Typical tower, self-build mostly on Gigabyte pieces:
CPU: Intel Core i5-2310, 2.9GHz, 6MB;
Motherboard: GIGABYTE GA-Z68A-D3-B3;
RAM: Viper Xtreme Series Division 2, 2x4GB, DD3-1866MHz;
HD: WD Caviar Green, 1TB, 7200;
Graphics: Gigabyte GeForce GTX 460 1024 MB DDR5;

nVidia on proprietary driver 310.

Works like a charm...