I would recommend 3 things.
The first would be eVGA... but since it's hard to find in AU. anything other then XFX. Forget factory OC. You can OC it yourself. There are tons of good tools out there to use.
Second consider going with (2 X 1GIG) RAM... OCin' ram or not?
Third - Look into the Seasonic S12-600watt PSU. Dual 18a 12v rails, Active PFC, SLI certified, up to 80% efficiency. My buddy just got this PSU and after some multimeter testing... it's darn impressive... Solid as a rock.
BTW. Very nice choice on cases... I love that case. It's not a flashy, gamers case, with a side window... but it's made really well, has great cooling and has a fantasic internal design...