A new GeForce GTX480 goes for $210
at Newegg. A hot-clocked Radeon HD7850 for around $260
provides the same performance for less than 1/3 as much power and heat. You could also get the same performance from a new GeForce GTX570 for around $275
Your used GeForce GTX480 would provide the same gaming performance.
i7-2600K, H70, P8P67-M Pro, 16 GiB, HD7950, SSD, 3 HD, Blu-ray, X-Fi Ti Pro, Antec P182, S75CF, 3007WFP+2001FP, RK-9000BR, MX518
i5-3570K, GeminII-S524, P8Z77-M Pro, 16 GiB, HD7770, SSD, 2 HD, Blu-ray, InifiniTV4, NSK2480, 55" TV; Asus UX32VD