NVIDIA GeForce GTX 765M SLI
The NVIDIA GeForce GTX 765M SLI is a high-end DirectX 11-compatible graphics solution for laptops, consisting of two GeForce GTX 765M. Each card has a 28nm GK106 core based on the Kepler architecture. The clocks for the SLI-setup are identical to a single GTX 765M. With SLI, each card usually renders a single frame (AFR mode). Therefore, it may suffer from micro stuttering in low fps ranges below 30fps. This happens because of irregular delays between two sequential frames.
The Kepler architecture is the successor to the Fermi architecture that first appeared in laptops with the GeForce 400M series. The GK106 Kepler core offers five shader blocks, called SMX, that are clocked at the same speed as the central core. In the GTX 765M, only four blocks are activated (= 768 CUDA-Cores for each 765M). Although the Kepler architecture can utilize more shader cores than a Fermi chip, its shaders can be up to twice as power efficient. However, due to the missing hot clock of the shader domain, two shaders of a Kepler chip are of similar speed to one shader of a Fermi chip (as the latter is clocked twice as fast).
PCIe 3.0 is now supported by the mobile Kepler series and an optional Turbo mode can automatically overclock the Nvidia card by a theoretical 15 percent if the laptop cooling system allows it. The implementation of this boost mode is done in the BIOS, but it is ultimately dependent upon the manufacturer of the laptop.
The graphics performance of the GeForce GTX 765M SLI is about 70 - 80 percent above a single GTX 765M, making it as fast as a single GeForce GTX 680M. Therefore, most games as of 2013 are playable at the highest detail setting and in FullHD resolution. In many cases it is even possible to activate additional anti-aliasing.
The feature set includes support for up to 4 active displays. Furthermore, high resolution monitors of up to 3840x2160 pixels can now be connected using DisplayPort 1.2 or HDMI 1.4a if available. HD-Audio codecs, such as Dolby TrueHD and DTS-HD, can be transmitted via bitstream mode through the HDMI port. However, as most laptops will feature Optimus, the integrated GPU will likely have direct control over the display ports and may limit the feature set available by the Nvidia Kepler cards.
The 5th generation PureVideo HD video processor (VP5) is also integrated in the GK106 core and offers hardware decoding of HD videos. Common codecs such as MPEG-1/2, MPEG-4 ASP, H.264 and VC1/WMV9 are fully supported up to 4K resolutions while VC1 and MPEG-4 are supported up to 1080p. Two streams can be decoded in parallel for features such as Picture-in-Picture. Another novelty is the inclusion of a dedicated video encoding engine similar to Intel QuickSync that can be accessed by the NVENC API.
The power consumption of the GeForce GTX 765M SLI should double that of a single 765M at about 120 - 130 W including the boards and memory. Therefore, the dual cards are well-suited for large desktop replacements.
|GeForce GTX 700M Series|
|Pipelines||1536 - unified|
|Core Speed||850 MHz|
|Memory Speed||4000 MHz|
|Memory Bus Width||2x 128 Bit|
|Max. Amount of Memory||2x 2048 MB|
|DirectX||DirectX 11, Shader 5.0|
|Transistor Count||2x 2540 Million|
|Features||Optimus, SLI, PhysX, Verde Drivers, CUDA, 3D Vision, 3DTV Play|
|Date of Announcement||30.05.2013|