Having problems with my Sapphire hd 7770 ghz edition

ANIR0X2K00L

Honorable
Mar 10, 2013
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I recently bought a sapphire hd 7770 ghz edition(non oc) and i cant get much overclocks out of it. All review sites are able to get better clocks from hd 7770, i even increased the voltages using gpu tweek as it was the only software that let me, still i am unable to get stable clocks which are significantly higher or more than 50 mhz.

This is my card:http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Here is an example of clocks that are said to be easily achievable with this card:
https://docs.google.com/spreadsheet/ccc?key=0AmLKAgEko3...

Is this a prob with my card and should i get it replaced, or is it something else. Please help quick as its been only 3 days since purchase and i can hopefully easily get it replaced. Or is there something wrong with the way i am overclocking.
 

ANIR0X2K00L

Honorable
Mar 10, 2013
69
0
10,640


Intel core 2 duo e7400
Intel dg41ty
4gb ddr2 800mhz
Sapphire hd 7770 ghz edition
500 w psu
500gb hdd