NVIDIA Quadro K620M vs NVIDIA Quadro K3100M

NVIDIA Quadro K620M

The Nvidia Quadro K620M is a DirectX 11 and OpenGL 4.5-compatible graphics card for mobile workstations. It is a Maxwell-based GPU built on the GM108 chip with 384 shader cores and manufactured in 28 nm by TSMC. The Quadro K620M is the successor to the significantly slower Quadro K610M. Usually, the GPU comes with 2 GB DDR3 memory clocked at 1000 MHz (2000 MHz effective, 16 GB/s). 

The Quadro series offers certified drivers that are optimized for stability and performance in professional applications like CAD or DCC. OpenGL performance, for example, should be significantly better than with GeForce graphics cards of similar specifications.

Architecture

Compared to Kepler, Maxwell has been optimized in several details to increase power efficiency. Smaller Streaming Multiprocessors (SMM) with only 128 ALUs (Kepler: 192) and an optimized scheduler should lead to better utilization of the shaders. Nvidia promises that a Maxwell SMM with 128 ALUs can offer 90% of the performance of a Kepler SMX with 192 ALUs. GM108 features 3 SMMs and thus 384 shader cores, 24 TMUs and 8 ROPs (64-bit interface).

Another optimization is the massively enlarged L2 cache. The larger size can reduce some of the memory traffic to allow for a relatively narrow memory interface without significantly hurting performance.

GM108 supports DirectX 11.2 (feature level 11.0 only) as well as DirectX 12.

Performance

Due to their identical specifications, the Quadro K620M offers a similar 3D gaming performance as the consumer GeForce 840M. Most games from 2014/2015 will run fluently in low or medium settings. Compared to other Quadro GPUs, the K620M performs almost similar to the older K1100M.

Features

The feature set should include support for up to 4 active displays. High-resolution monitors of up to 3840x2160 pixels can be connected using DisplayPort 1.2 or HDMI 1.4a (HDMI 2.0 not supported). 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.

Using CUDA or OpenCL, the cores of the Quadro K620M can be used for general calculations.

GM108 integrates the sixth generation of the PureVideo HD video engine (VP6), offering a better decoding performance for H.264 and MPEG-2 videos. Of course, VP6 supports all features of previous generations (4K support, PIP, video encoding via NVENC API).

Power Consumption

The power consumption of the Quadro K620M should be about 30 W including the board and memory components. Therefore, the GPU is best suited for laptops 13 - 14-inches in size and above. The K620M also supports Optimus to automatically switch between an integrated graphics card and the Nvidia GPU.

NVIDIA Quadro K3100M

The NVIDIA Quadro K3100M is a DirectX 11 and OpenGL 4.3 compatible graphics card for mobile workstations. It is a Kepler-based GPU built on the GK104 chip with 768 out of 1536 shader cores activated and is manufactured in 28nm at TSMC. The Quadro K3100M is built for the Intel Shark Bay generation (Haswell) and is a successor to the Quadro K3000M (Chief River platform). As a new feature, PCIe 3.0 is supported for the first time. The K3100M usually comes with 4 GB GDDR5 VRAM clocked at 800 MHz (3200 MHz effective, 102.4 GB/s). 

The Quadro series offers certified drivers that are optimized for stability and performance in professional applications like CAD or DCC. OpenGL performance, for example, should be significantly better than with GeForce graphics cards of similar specifications.

Architecture

The Kepler architecture is the successor to the Fermi architecture that first appeared in laptops with the GeForce 400M series. The GK104 Kepler core offers eight shader blocks, called SMX, that are clocked at the same speed as the central core. In the K3100M, 4 of 8 blocks are active leading to the 768 CUDA cores. Although more shader cores are available in the Kepler architecture as compared to the Fermi design, the Kepler shaders are still expected to be up to twice as power efficient. However, due to the missing hot clock of the shader domain, two shaders of a Kepler chip offer similar performance to just one shader of a Fermi chip (as the latter is clocked twice as fast).

Performance

The performance is clearly above the old Quadro K3000M and just slightly below the Quadro K4000M. This places the K3100M somewhat below the consumer GTX 765M GPU. Nevertheless, most demanding games of 2013 will run fluently with high to very high details.

Features

The improved feature set now includes support for up to 4 active displays. Furthermore, high resolution monitors of up to 3840 x 2160 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.

Using CUDA or OpenCL 1.2, the cores of the Quadro K3100M can be used for general calculations.

The 5th generation PureVideo HD video processor (VP5) is also integrated in the GK104 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 Quadro K3100M is rated at a TGP of 75 W including the board and memory components. Therefore, the card is suited for large notebooks with 17-inch displays or greater.