scratch everythingg ive said about the graphics card and have an open mind.... i checked out some reviews for the x600 and basically, more or less, its the pci-e version of the 9600 series... soo ur basically gettin a 9600, non pro or xt. It will be ok, but once again in the near future with games such as STALKER, ur not gona be able to play it too well...
so, YES ur card will run doom 3 and hl2, but at medium settings