Hey emunebtk,

IMO i would just pick one of these up SAPPHIRE Radeon HD 7970 3GB GDDR5 PCI Express 3.0 x16 Video Card OC'ed  

$329.99- $20MIR-Your Getting A Brand New Card, therefore there are no risks involved unlike with USED Hardware. Plus You get a Warranty and a 30-day refund on the NewEgg Site.

Use This Promo-Code in the checkout and receive another $10 off-- NEWCUSTOMER06

http://www.newegg.com/Product/Product.aspx?Item=N82E16814202008


I've Build Over 10 Bitcoins rigs with 7970's so feel free to PM Me or you can request a Live Chat Session From Our Website--- www.TheBitcoinMiningOutlet.com

We sell all of the necessary parts for building a miner PLUS We also have a STEP-BY-STEP Guide on the Site Too.