I actually happen to own a HD7950, paired with a Phenom II 1055T, and 8GB RAM. This card is an absolute monster and i have absolutely no regrets spending the extra dollars getting it, i paid 330USD for the Gigabyte version show here:http://www.newegg.com/Product/Product.aspx?Item=N82E16814125414&Tpk=Gigabyte%20HD%207950
This has a Tri-Fan Windforce aftermarket cooler built right into it already so i would highly recmmend this, my case has a 200mm fan, and 4 120mm fans and this thing runs cool as hell under load, pardon my language. I get a steady 45C on games like borderlands, and it goes up to 60C on BF3 after playing for a 30mins or more, but thats the highest ive seen, and i play them ALL on Ultra-Maxed with 8xAA and 16xAA (Skyrim), ect
Edit: I did also want to mention that the 7870 has 256-bit Bandwidth port, while the 7950 has a 384-bit port, the Bandwidth gets a huge jump goign from 120GB/s to 240GB/s which is further future proofing the purchase. As a proud owner of one of these, it has NOT let me down! Good luck, man i hope this helped some!