There are affordable used units out there, but their processing power is literally less than half of their GeForce siblings (which do have the same GPU cores and often even less RAM!) These do support nvidia's tiling and overlapping software, Mosaic, and even edge-blending, which is good, but at this price you'd expect a lot more performance. Nvidia Quadro - These are virtually GeForce cards with lowered clock speeds, and a pricetag premium that is so high, you might as well buy a car instead. Short of watching films, they are not good for anything. Matrox - Second hand cards for dual-head are cheap, but these lack any sort of processing power. The only actually working solutions I found:

So I've been looking up what I could find regarding edge-blending with a PC for gaming as well as movies, and based on what GPU manufacturers offer, I have come to a simple conclusion: GPU manufacturers are all money-grubbing *********.