@ Jakestriker
Probably a wise move. There comes a point that you end up just putting good money into an old system, and you still end up with an old system.
Of those 2 boards, I would recommend the Gigabyte. I have had both. (long story I won't bore you with here) I returned the Asrock and kept the Gigabyte after seeing the difference. Better quality. Better design. Oh, and the Asrock cut my finger. Heat sinks were sharp as razors.
@Surihtanil
I too have a PhII X4 965BE on another machine (@ 4.0 Ghz), and it's running a R9-280. I tried several benchmark pgms and games, and have not found one that causes the old Ph II to bottle neck the R9-280 yet. I never see it hit 100% usage, while the card will often hit 100% usage depending on the game/benchmark. That tells me the CPU is not bottlenecking the card.