NVIDIA GeForce 940MX vs AMD Radeon RX 540 vs AMD Radeon RX 580 (Desktop)

NVIDIA GeForce 940MX

The Nvidia GeForce 940MX is a mid-range laptop graphics card with DirectX 12 support (FL 11_0). It has been announced in the first quarter of 2016 and is the refresh of the GeForce 940M. Compared to the older card, the new one is based on the same chip but now supports faster GDDR5. Therefore, it is similar to the Maxwell GPU in the Microsoft Surface Book but with more memory and higher clock speeds. However, most notebook vendors will use the slower DDR3 version of the 940MX that clocks only a few percent faster than the old GeForce 940M (1122 versus 1072 MHz base clock e.g.). 

For the GDDR5 version of the 940MX there appears to be also a variant with the GM107-B chip with 512 shaders instead of the 384 but lower clock speeds. The 940MX in the Acer Aspire E5-774G e.g. featured 512 shader cores (GM107) clocked at 795 - 861 MHz. The Dell Inspiron 17 7778 version however had the GM108 chip with 384 shaders clocked at 1083 - 1189 MHz.

The performance greatly depends on the used graphics memory and chip. According to our benchmarks (see below), the DDR3 version is very similar to the old 940M (due to only minor increased clock rates). The GDDR5 version however pushes ahead 20% (even 30% if paired with a fast desktop quad-core, but we lack 940M reference scores). Therefore, demanding games from 2015 should run fluently in low to medium settings and WXGA resolution. 

The TDP of the card should be rated at about 15 to 30 Watt (depending on the version, clock speeds and memory). Therefore, the GPU is best suited for laptops from 13-inch and up.

AMD Radeon RX 540

The AMD Radeon RX 540 is mobile mid-range graphics card for laptops based on the Polaris 12 chip (most likely). It is manufactured in an improved 14 nm FinFET process at Globalfoundries. The performance should be between the Radeon Pro 450 and 455 in the MacBook Pro 2016 range that is also based on the Polaris architecture. AMD specifies the RX 450 at 1.2 TFLOPS (Pro 450 1 TFLOP, Pro 455 1.3 TFLOPs). Compared to Nvidia graphics cards, the gaming performance should be between the GeForce GTX 950M and GTX 960M.

The features of the Radeon RX 540 are identical to the faster RX 460 and all other Polaris chips. See more details on the Polaris architecture here.

The power envelope of the faster Radeon Pro 460 is rated at 35 Watt according to the AMD blog post. Due to the slower specs, the Radeon RX 540 use slightly less.

AMD Radeon RX 580 (Desktop)