Tom's Hardware Guide posted a Mainstream Graphics Card Roundup
When it comes to graphics cards, the upper crust of the mid-range is perhaps your best bet for snagging great performance at a reasonable price. In order to deliver the goods without breaking the bank, vendors usually equip their cards with enhanced cooling solutions or a bit of extra graphics RAM.Mainstream Graphics Card Roundup
If you're only comparing 3D performance, the difference between these mid-range cards and those you'd find at the very top of our latest graphics charts is less than what you might think. While the GeForce GTX 285 may be the fastest single-GPU card around, a GeForce GTX 260 or a Radeon HD 4870 doesn't lag behind by much. If you can live with that relatively minor difference, you stand to save between $100 to $150 or more.