AMD Radeon HD 8970M vs AMD Radeon R9 M280X

AMD Radeon HD 8970M

The AMD Radeon HD 8970M is a 28nm DirectX 11 graphics card based on the GCN (Graphics Core Next) architecture. Built primarily for large laptops, the advanced card is positioned near the top of the high-end category as of 2013. Its performance and feature set are similar to the HD 7970M, as the 8970M shares the same core and only features a higher maximum core clock.

The design of the Radeon 8900M series has its roots to the Pitcairn chip as found on the desktop Radeon HD 7870. The 8970M in particular is similar to its desktop Radeon HD 7870 counterpart with 1280 1D shader cores and 80 texture units, but has a core clock of only 900 MHz (boost) versus the 1000 MHz clock of the HD 7870. Compared to the HD 7970M, the 8970M shares the same base clock rate but with a 50 MHz higher Turbo clock for a 6% increase (1.01 TFLOPS vs. 1.07 TFLOPS) in raw SP calculations. As a result, general performance of the HD 8970M is somewhere between the 7850 and 7870 desktop Radeon cards.

When compared to mobile Nvidia GPUs, the HD 8970M performs significantly faster than the GeForce GTX 675M and slightly above the Nvidia GeForce GTX 680M. Therefore, almost all demanding games of 2013 will run fluently on very high details and 1080p resolution.

Features of the 8970M include the new UVD3 video decoder for decoding MPEG-4 AVC/H.264, VC-1, MPEG-2, Flash, Multi-View Codec (MVC) and MPEG-4 part 2 (DivX, xVid) HD videos directly from the AMD GPU.

The 8900M series also supports automatic graphics switching between the integrated GPU and discrete GPU. Called Enduro, the technology supersedes AMD's Dynamic Switchable Graphics and is similar to Nvidia's Optimus. Furthermore, the 8970M can directly support up to 6 connected monitors using Eyefinity Technology if Enduro is disabled.

Other features of the 8900M series include ZeroCore for reducing power consumption when the display is turned off. Power Gating, however, is not supported according to AMD. PowerTune allows automatic overclocking and underclocking of the graphics card as long as the GPU is within its TDP range. For example, the chip may be underclocked when running FurMark and OCCT, but will overclock in certain games like Lost Planet, Crysis or Resident Evil 5.

The integrated HD audio processor is able to transmit HD Audio (TrueHD or DTS Master Audio) over HDMI and DisplayPort (e.g., for Blu-Ray videos). Additionally, it now allows audio to output simultaneously and in parallel to multiple devices with the new Discrete Digital Multipoint Audio (DDMA) feature.

Power consumption of the 8970M is in the same ballpark as the GeForce GTX 680M. The subsequently large heat output suits the 8970M as an option only for large laptops or DTRs (desktop replacements) equipped with relatively powerful cooling solutions.

AMD Radeon R9 M280X

The AMD Radeon R9 M280X is a 28 nm DirectX 12 graphics card based on the GCN (Graphics Core Next) architecture. Built primarily for large laptops, the card is positioned in the upper mid-range category as of 2014. It is based on the Saturn chip (Bonaire codename for Desktop R7 260(X)) and clocked at 900 to 1000 MHz (Boost). The R9 M280X offers 896 shader cores, 56 TMUs, 16 ROPs and a 128 Bit memory interface for up to 4 GB GDDR5 memory (1375 MHz / 5500 MHz effective, 88 GB/s).

The performance of the Radeon R9 M280X is on par with the Nvidia GeForce GTX 850M or GTX 950M. Games from 2015 therefore should run in middle to high settings in 1080p. Some more demanding games like Assassin's Creed Unity may only run fluently in reduced settings.

The 640 shader cores can be used with OpenCL 1.2 for general-purpose calculations (as 10 compute units).

Features of the R9 series include video decoding via UVD3 for decoding MPEG-4 AVC/H.264, VC-1, MPEG-2, and Flash directly from the AMD GPU. Multi-View Codec (MVC) and MPEG-4 part 2 (DivX, xVid) HD videos are now compatible as well.

The Radeon R9 also supports automatic graphics switching between the integrated GPU and discrete GPU, called Enduro. The technology supersedes AMD's Dynamic Switchable Graphics and is similar to Nvidia's Optimus. Other features include ZeroCore for reducing power consumption when the display is turned off .

The Power consumption of the R9 M280X is not specified but should be around 70 to 80 Watt and therefore, the GPU is only suited for larger laptops and DTRs.