I found (googled) this system integrator :
www.IronsideComputers.com ( Las Vegas, NV )
the web site has a large listing of Gaming and Performance PCs ( desktops ).
One of the listed systems looks suitable for Cuda development :
processor : Intel Core i7 2600k 3.4GHz Turbo 3.8GHz
motherboard : Gigabyte P67A-D3-B3
memory : 8GB (2x4GB) DDR3 1333MHz
GPU : GeForce GTX 580 1.5GB
primary hard drive : 1TB 7200 RPM
power supply: Raidmax Blackstone 700 Watt
heatsink : Cooler Master TX3
OS : Linux , RedHat 6.0 or openSUSE
Has anyone ordered a similar system from IronsideComputers and successfully installed Cuda SDK 4.0 on it ?