HardOCP tested nine graphics cards from NVIDIA and AMD in Borderlands to compare the performance and image quality, you can check it out over here.
This evaluation will see 9 video cards from NVIDIA and AMD. From NVIDIA, we have the GeForce GTX 295, the GeForce GTX 285, the GeForce GTX 275, and the GeForce GTS 250. From AMD, we have the ATI Radeon HD 4870 X2, the Radeon HD 5870, the Radeon HD 5850, the Radeon HD 5770, and the Radeon HD 5750. The Radeon HD 4000 series has mostly been dropped from this evaluation because any gamers looking to upgrade to an ATI video card should be considering the new Radeon HD 5000 series products for their excellent performance and feature sets.