In terms of overall gaming performance, the graphical capabilities of the Nvidia GeForce 9800 GT are very slightly better than the AMD Radeon HD 6670.

The Radeon HD 6670 has a 200 MHz higher core clock speed than the GeForce 9800 GT, but the GeForce 9800 GT has 32 more Texture Mapping Units than the Radeon HD 6670. As a result, the GeForce 9800 GT exhibits a 14.4 GTexel/s better Texture Fill Rate than the Radeon HD 6670. This still holds weight but shader performance is generally more relevant, particularly since both of these GPUs support at least DirectX 10.

The Radeon HD 6670 has a 200 MHz higher core clock speed than the GeForce 9800 GT, but the GeForce 9800 GT has 8 more Render Output Units than the Radeon HD 6670. As a result, the GeForce 9800 GT exhibits a 3.2 GPixel/s better Pixel Fill Rate than the Radeon HD 6670. However, both GPUs support DirectX 9 or above, and pixeling performance is only really relevant when comparing older cards.

The Radeon HD 6670 was released over a year more recently than the GeForce 9800 GT, and so the Radeon HD 6670 is likely to have better driver support, meaning it will be more optimized for running the latest games when compared to the GeForce 9800 GT.

The Radeon HD 6670 has 512 MB more video memory than the GeForce 9800 GT, so is likely to be much better at displaying game textures at higher resolutions. This is supported by the fact that the Radeon HD 6670 also has superior memory performance overall.

The Radeon HD 6670 has 6.4 GB/sec greater memory bandwidth than the GeForce 9800 GT, which means that the memory performance of the Radeon HD 6670 is marginally better than the GeForce 9800 GT.

The Radeon HD 6670 has 480 Shader Processing Units and the GeForce 9800 GT has 112. However, the actual shader performance of the Radeon HD 6670 is 192 and the actual shader performance of the GeForce 9800 GT is 168. The Radeon HD 6670 having 24 better shader performance is not particularly notable, as altogether the GeForce 9800 GT performs better when taking into account other relevant data.

The Radeon HD 6670 transistor size technology is 25 nm (nanometers) smaller than the GeForce 9800 GT. This means that the Radeon HD 6670 is expected to run slightly cooler and achieve higher clock frequencies than the GeForce 9800 GT. While they exhibit similar graphical performance, the Radeon HD 6670 should consume less power than the GeForce 9800 GT.

The Radeon HD 6670 requires 66 Watts to run and the GeForce 9800 GT requires 105 Watts. We would recommend a PSU with at least 400 Watts for the Radeon HD 6670 and a PSU with at least 400 Watts for the GeForce 9800 GT. The GeForce 9800 GT requires 39 Watts more than the Radeon HD 6670 to run. The difference is significant enough that the GeForce 9800 GT may have a slight adverse affect on your yearly electricity bills in comparison to the Radeon HD 6670.