This is the fastest laptop you can buy for games in this price range, probably all the way up to $1000. There's a couple other models on sale at DSE but I think this one stands out the most.
Compared to the Lenovo previously posted (http://www.ozbargain.com.au/node/52204) it could be up to 50% faster in games
Radeon HD 6770M 480@725MHz 1600MHz (dv6-6023TX)
Radeon HD 6630M 480@485MHz 800MHz (Lenovo E420/E520)
"The HP Pavilion dv6-6023TX Notebook features a 15.6" High Definition HP BrightView LED screen as well as a 2nd generation Intel Core 5-2410M Processor, 640GB of Hard Drive and ATI Radeon HD 6770M 1GB GDDR5 Graphics making it a well rounded and high performing laptop computer."
Pity it does not have the i7-2630 cpu.