Yes that is strange as the 5770 is a mid range card and the 4890 is a high end card. The only thing the 5770 has over the 4890 is DX11 support. The only 5xxx cards faster than a 4890 are the 5850,5870 and the 5970. One reason for the price premium on the 5xxx cards is they just came out. If your a hardcore gamer I'd hold out for a 5850, 5870 or if money is no object a 5970. Anyone of the three should be able to handle the latest games at 1920x1080 resolution. Prices should come down once supply can keep up with demand.
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