Amd Phenom 9950 Black Edition 2,6Ghz boxed Processor ( getting ASAP, current CPU is Amd 64 x2 5200+ )
Any ( Propably Sapphires ) Radeon HD 4870
Have you checked to see if your board is capable of the cpu upgrade ?
The board comes with either a 4mb NVram chip or 8 mb ( which is what you'll need to have), you can tell the difference by the word "enhanced" appearing in the bios splash screen.
Now on to the video card, due to the borked BTX form factor dual slot cards will not fit without modifying the case.
You would need to create an extra expansion slot ( above the upper most existing slot ) and remove a good portion of the bottom of the heat sink .