Yes,
I am running two of the GTX 550 Ti 1GB (made by Evga) SLI'd together
plus 8GB ram DDR3 1600Mhz
Intel i5 Quad Core 3.3 Processor
Gigabyte Sniper M3 Motherboard
1TB Hard Drive
Liquid Cooling
6 Case fans W/ led's
DVD/CD-RW Combo Drive
and it is all overclocked running about 550 Watts