AMD Radeon HD 7630M vs AMD Radeon HD 7640G + HD 7670M Dual Graphics

AMD Radeon HD 7630M

The AMD Radeon HD 7630M (sometimes also called AMD Radeon HD 7630M) is a middle class graphics card for laptops in 2011. It is based on the same chip as the Radeon HD 6630M and the 6 SIMD blocks (= 480 shader) are clocked at 450 MHz. The card is still build in 40nm and supports DirectX 11.

The 480 Stream processors are still based on the 5D architecture similar to the 5000 series. Therefore, the number of shaders is not comparable to the 1D cores of current Nvidia GPUs. The Tessellation performance should be improved (like the desktop 6800 series) with the new cards. The Stream processors can be used with DirectX 11, OpenGL 4.1, DirectCompute 11 and OpenCL. With the later two the cores can also be used for general computations like transcoding videos.

The 3D performance should be similar to the Radeon HD 6630M due to the comparable clock rates and the 480 shaders. Therefore, demanding games of 2011 like Battlefield 3 or Anno 2070 are running only in low detail settings fluently. Games with less demanding 3D engines like CoD MW3 should also run in high details.

The new UVD3 video decoder supports the decoding of MPEG-4 AVC/H.264, VC-1, MPEG-2, Flash and now also Multi-View Codec (MVC) and MPEG-4 part 2 (DivX, xVid) HD videos on the graphics card.

Furthermore, the HD 7600M series integrates a HD audio controller to transmit HD Audio (TrueHD or DTS Master Audio) over HDMI and DisplayPort (e.g. for Blu-Ray videos).

The AMD HD3D Technology offers support for Blu-Ray 3D and 3D displays (integrated and external). However, the solution is not as mature as Nvidias 3D Vision.

Thanks to Eyefinity the graphics chip is able to theoretically drive up to 5 monitors simultaneously. However, this only works if the laptop features enough DisplayPort outputs.

The power consumption of the chip should be slightly below the Radeon HD 6630M and therefore suited for smaller laptops (13-14").

AMD Radeon HD 7640G + HD 7670M Dual Graphics

The AMD Radeon HD 7640G + HD 7670M Dual Graphics is the combination of a integrated AMD Radeon HD 7640G APU processor graphics card and a dedicated entry level AMD Radeon HD 7670M graphics card in CrossFire combination. It is called AMD Dual Graphics or asymmetric CrossFire and uses AFR (Alternate Frame Rendering) to render different frames on the two graphic cores. Therefore the combination also suffers from micro stuttering (different spaces between two images lead to stuttering altough the framerate is high enough for fluent gaming with only one GPU).

The performance of the Dual Graphics solution depends greatly on the driver support for the used games. In some games the performance may even degrade by 10-15% compared to using only the APU graphics card. Therefore, due to the micro stuttering and performance problems, Dual Graphics may impose more problems than bring performance gains. Only in a best case scenario the performance is similar to the GeForce GT 635M.

The features like PureVideo HD (UVD3) or OpenCL support are similar to the two graphics cards.

As both graphics cards are rendering frames, the power consumption is clearly higher than using only one GPU.