In terms of overall gaming performance, the graphical capabilities of the Nvidia Quadro K4000M are very slightly better than the AMD Radeon R9 M365X 4GB.

The R9 M365X has a 24 MHz higher core clock speed than the Quadro K4000M, but the Quadro K4000M has 40 more Texture Mapping Units than the R9 M365X. As a result, the Quadro K4000M exhibits a 23.1 GTexel/s better Texture Fill Rate than the R9 M365X. This still holds weight but shader performance is generally more relevant, particularly since both of these GPUs support at least DirectX 10.

The R9 M365X has a 24 MHz higher core clock speed than the Quadro K4000M, but the Quadro K4000M has 16 more Render Output Units than the R9 M365X. As a result, the Quadro K4000M exhibits a 9.2 GPixel/s better Pixel Fill Rate than the R9 M365X. However, both GPUs support DirectX 9 or above, and pixeling performance is only really relevant when comparing older cards.

The R9 M365X was released over three years more recently than the Quadro K4000M, and so the R9 M365X is likely to have far better driver support, meaning it will be much more optimized and ultimately superior to the Quadro K4000M when running the latest games.

The Radeon R9 M365X 4GB and the Quadro K4000M have the same amount of video memory, but are likely to provide slightly different experiences when displaying game textures at high resolutions.

The Quadro K4000M has 25.6 GB/sec greater memory bandwidth than the R9 M365X, which means that the memory performance of the Quadro K4000M is slightly better than the R9 M365X.

The Radeon R9 M365X 4GB has 640 Shader Processing Units and the Quadro K4000M has 960. However, the actual shader performance of the R9 M365X is 340 and the actual shader performance of the Quadro K4000M is 577. The Quadro K4000M having 237 better shader performance and an altogether better performance when taking into account other relevant data means that the Quadro K4000M delivers a noticeably smoother and more efficient experience when processing graphical data than the R9 M365X.

The Radeon R9 M365X 4GB requires 50 Watts to run and the Quadro K4000M requires 100 Watts. The Quadro K4000M requires 50 Watts more than the R9 M365X to run. The difference is significant enough that the Quadro K4000M may have a slight adverse affect on your yearly electricity bills in comparison to the R9 M365X.