In terms of overall gaming performance, the graphical capabilities of the AMD Radeon HD 4890 Sapphire Toxic 1GB Edition are marginally better than the AMD Radeon HD 6850 Sapphire 1GB Edition.

The HD 4890 has a 185 MHz higher core clock speed but 8 fewer Texture Mapping Units than the HD 6850. The lower TMU count doesn't matter, though, as altogether the HD 4890 manages to provide 1.2 GTexel/s better texturing performance. This still holds weight but shader performance is generally more relevant, particularly since both of these GPUs support at least DirectX 10.

The HD 4890 has a 185 MHz higher core clock speed than the HD 6850, but the HD 6850 has 16 more Render Output Units than the HD 4890. As a result, the HD 6850 exhibits a 9.4 GPixel/s better Pixel Fill Rate than the HD 4890. However, both GPUs support DirectX 9 or above, and pixeling performance is only really relevant when comparing older cards.

The HD 6850 was released over a year more recently than the HD 4890, and so the HD 6850 is likely to have better driver support, meaning it will be more optimized for running the latest games when compared to the HD 4890.

The Radeon HD 4890 Sapphire Toxic 1GB Edition and the Radeon HD 6850 Sapphire 1GB Edition have the same amount of video memory, but are likely to provide slightly different experiences when displaying game textures at high resolutions.

The HD 4890 has 6.4 GB/sec greater memory bandwidth than the HD 6850, which means that the memory performance of the HD 4890 is marginally better than the HD 6850.

The Radeon HD 4890 Sapphire Toxic 1GB Edition has 800 Shader Processing Units and the Radeon HD 6850 Sapphire 1GB Edition has 960. However, the actual shader performance of the HD 4890 is 538 and the actual shader performance of the HD 6850 is 372. The HD 4890 having 166 better shader performance and an altogether better performance when taking into account other relevant data means that the HD 4890 delivers a marginally smoother and more efficient experience when processing graphical data than the HD 6850.

The HD 6850 transistor size technology is 15 nm (nanometers) smaller than the HD 4890. This means that the HD 6850 is expected to run slightly cooler and achieve higher clock frequencies than the HD 4890. While they exhibit similar graphical performance, the HD 6850 should consume less power than the HD 4890.

The Radeon HD 4890 Sapphire Toxic 1GB Edition requires 190 Watts to run but there is no entry for the Radeon HD 6850 Sapphire 1GB Edition. We would recommend a PSU with at least 500 Watts for the HD 4890 and a PSU with at least 500 Watts for the HD 6850. The two GPUs have been recommended a PSU with the same amount of wattage. As such, there is no need to worry about which will more significantly affect your yearly electricity bills.