Tumn1s :
Whoever setup the mining benchmarks for this article doesn't have a clue what they're doing... I get 450kh/s out of my R9 270x on stock clocks. Learn how to configure CGminer, thanks.
I've read a lot of people "claiming 450kH/s" from a card with 1,280 shaders but yet to see proof. Until then, it's bs. Like a lot of people on the Litecoin Wiki page. No validations and for some reason want to lie about it.
It's a 300-350kH/s card with matching WU's or close to it (.9). Getting 450kH/s and -/+300 WU's means the hashrate is junk.
I can see people getting 400+kH/s with the 7870XT with the Tahiti LE chip but not Pitcairn. Needless to say, every card is different from the components used to it's firmware. A simple Google will easily show that most with Pitcairn GPU's with 1,280 shaders average hashrate is right around 300kH/s.