2 VisionTek 6950s $320 together, or $170 each (plus shipping) - These GPUs both mine at speeds up to 450khps. They are at the stock 1408 shaders. These cards do not feature a dual bios, so I haven't tried to flash unlocked shaders onto either of them. They are 2 slot cards, but they have a massive heatsink so they take up 3 slots of space. These are the 1GB edition cards which might seem a little small but they still could handle games with up to 4xMSAA without VRAM becoming a problem. Finally, as for temperatures these cards are great. Under full load the cards only reach 58 degrees Celsius with ambient temperatures of 75 degrees F and a fan speeds of ~55%.
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