French computer website Hardware.fr has published its latest list of computer hardware failure rates, you can check it out over here. It's in French but with the help of Google's Translator it shouldn't be too hard to understand, each page gives failure rates for the most popular brands and also provides failure rates for specific components.
The data originates from a large French e-tailer, it covers returns created before October 2010 for hardware sold between October 1, 2009 and April 1, 2010. The brand failure rates are compiled using a minimum sample of 500 sales, while model failure rates are calculated using a minimum sample of 100 sales.
In the motherboard market there doesn't seem to be a lot of difference between manufacturers: