Distro, Mobo, Processor for Cuda development Stable HW and distro needed for Cuda development

Hello,
I would like to build a cheap stable system which runs a linux distro (preferably Ubuntu 11.04) though I am up for anything.
I am doing Cuda development for numerical computation so a single or dual core processor is fine.
My old mobo has been kernel paninc’ing on Ubuntu 10.10 and 11.04. I even tried Windows 7- no go – so its time to upgrade.
I heard that gigabyte motherboards are good with linux? Any thoughts on processors? I want to keep it less than $300 for the mainboard and processor. (usb 3.0 would be nice).
I already have a Quadro 600. What Linux distro’s, processors, mobo’s, chipsets ram and nic are stable?? I you are doing Cuda development and have something stable that’s even better.

Also the mobo must be ATX to fit in a 3U rack with a 550W ps.

I could try disto specific forum’s but if I don’t get a system that is stable for Quadro600/Cuda development the system is as good as a paper weight to me!

Thanks in advance. External Image

~Hell is a never ending series of kernel panic’s without an upgrade path!