In terms of overall gaming performance, the graphical capabilities of the AMD Radeon R9 390X XFX Double Dissipation Black 8GB Edition are significantly better than the AMD Radeon R9 380.

The R9 390X has a 120 MHz higher core clock speed and 64 more Texture Mapping Units than the Radeon R9 380. This results in the R9 390X providing 83.2 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 R9 390X has a 120 MHz higher core clock speed and 32 more Render Output Units than the Radeon R9 380. This results in the R9 390X providing 38.8 GPixel/s better pixeling performance. However, both GPUs support DirectX 9 or above, and pixeling performance is only really relevant when comparing older cards.

Both the Radeon R9 390X XFX Double Dissipation Black 8GB Edition and the Radeon R9 380 were released at the same time, so are likely to be quite similar.

Both GPUs exhibit very powerful performance, so it probably isn't worth upgrading from one to the other, as both are capable of running even the most demanding games at the highest settings.

The R9 390X has 6144 MB more video memory than the Radeon R9 380, so is likely to be much better at displaying game textures at higher resolutions. This is supported by the fact that the R9 390X also has superior memory performance overall.

The R9 390X has 208 GB/sec greater memory bandwidth than the Radeon R9 380, which means that the memory performance of the R9 390X is massively better than the Radeon R9 380.

The Radeon R9 390X XFX Double Dissipation Black 8GB Edition has 2816 Shader Processing Units and the Radeon R9 380 has 1792. However, the actual shader performance of the R9 390X is 2609 and the actual shader performance of the Radeon R9 380 is 1478. The R9 390X having 1131 better shader performance and an altogether better performance when taking into account other relevant data means that the R9 390X delivers a massively smoother and more efficient experience when processing graphical data than the Radeon R9 380.

The Radeon R9 390X XFX Double Dissipation Black 8GB Edition requires 300 Watts to run and the Radeon R9 380 requires 190 Watts. We would recommend a PSU with at least 750 Watts for the R9 390X and a PSU with at least 500 Watts for the Radeon R9 380. The R9 390X requires 110 Watts more than the Radeon R9 380 to run. The difference is significant enough that the R9 390X may have an adverse affect on your yearly electricity bills in comparison to the Radeon R9 380.