I'm building a new system with phenom ii x3 720 black edition and GIGABYTE GA-MA790GPT-UD3H AM3 790GX HDMI ATX AMD Motherboar. As for graphics card, I am thinking of ATI 4670 1G or Geforce 9800 GT 512M. For ATI 4670 card, can I crossfire it with my onboard HD3300 graphics card? How much performance improvement could there be? And, I know with 9800 I won't be able to crossfire. But if considering using only one graphics card, is 9800 a good solution for an AMD platform? Will it outperform the 4670? Thank you very much!
if i'm not mistaken you can't crossfire HD4670 with on board 3300. they can only be combined with some weak card from 3000 series but i don't remember the exact model. as for pure performance 9800GT will be better than HD4670 but 9800GT will need more power than HD4670 as 9800GT need 6 pin power connector.however there are some low power version of 9800GT that doesn't need extra power connector.
and don't worry about graphic card compatibility with intel/AMD processor or motherboard. nvidia cards will work on both platform and the same goes with ATI cards