AMD Radeon HD 8790M vs NVIDIA GeForce GT 720M vs AMD Radeon HD 8770M

AMD Radeon HD 8790M

The AMD Radeon HD 8790M (sometimes known as the ATI Mobility Radeon HD 8790) is a DirectX 11.1 graphics card for laptops. It is based on the Mars chip (28nm GCN architecture) with 384 shader cores, 24 TMUs, and 8 ROPs. The core is clocked at 850 MHz (900 MHz Boost) with GDDR5 VRAM at 1125 MHz (4500 MHz effective).

The performance of the Radeon HD 8790M is similar to the Nvidia GeForce GTX 660M or GT 750M and therefore in the upper mid-range category. Most games of 2013 can be played fluently in medium or high details and the WXGA resolution of 1366 x 768 pixels.

The 384 shaders can be used with OpenCL 1.2 for general-purpose calculations (as 6 compute units). Compared to old TeraScale 2 chips, the GCN-based Mars architecture offers improved performance in this framework.

Features of the 8790M 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 8700M 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 8790M can directly support up to 2 connected monitors using Eyefinity Technology if Enduro is disabled.

Other features of the 8700M series include ZeroCore for reducing power consumption when the display is turned off and Power Gating to power down areas of the chip that are not used. PowerTune allows automatic overclocking and underclocking of the graphics card as long as the GPU is within its TDP limit. 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.

The power consumption should be slightly higher than the previous 7690M chip when under load (2 Watt difference according to the desktop setup from Techreport). However, the 8790M can potentially draw less power when idle (if not disabled by Enduro). Overall, the 8790M is best suited for 15-inch notebooks or bigger.

NVIDIA GeForce GT 720M

AMD Radeon HD 8770M

The AMD Radeon HD 8770M (sometimes known as the ATI Mobility Radeon HD 8770) is a DirectX 11.1 graphics card for laptops. It is based on the Mars chip (28nm GCN architecture) with 384 shader cores, 24 TMUs, and 8 ROPs. The core is clocked at 775 MHz (or up to 825 MHz with Boost) with GDDR5 VRAM at 1125 MHz (4500 MHz effective).

The performance of the Radeon HD 8770M is in range of the GeForce GT 730M. Current and demanding games like Far Cry 3 will run fluently in medium resolutions and detail settings (as of 2013).

The 384 shaders can be used with OpenCL 1.2 for general-purpose calculations (as 6 compute units). Compared to old TeraScale 2 chips, the GCN-based Mars architecture offers improved performance in this framework.

Features of the 8770M 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 8700M 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 8770M can directly support up to 2 connected monitors using Eyefinity Technology if Enduro is disabled.

Other features of the 8700M series include ZeroCore for reducing power consumption when the display is turned off and Power Gating to power down areas of the chip that are not used. PowerTune allows automatic overclocking and underclocking of the graphics card as long as the GPU is within its TDP limit. 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.

The power consumption should be similar to the old HD 7670M. As a result, the 8770M is best suited for 13-inch notebooks or larger.