Intel Iris Plus Graphics 655 vs AMD Radeon RX Vega M GH vs Intel Iris Plus Graphics 640

Intel Iris Plus Graphics 655

AMD Radeon RX Vega M GH

The AMD Radeon RX Vega M GH is an integrated GPU in the fastest Intel Kaby-Lake-G SoC. It combines a Kaby-Lake processor, a Vega graphics card and 4 GB HBM2 memory on a single package. The graphics card offers 24 CUs (1536 shaders) and is clocked from 1063 - 1190 MHz.

Currently it looks like the GPU is a mixture of Polaris (Shaders?) and Vega (HBM memory controller at least). E.g. the graphics card is called Polaris 22 internally. Detailed information on the Vega architecture can be found in our dedicated article about the Raven Ridge architecture.

The performance of the Vega M GH should be slightly slower than a dedicated Nvidia GeForce GTX 1060 for laptops according to benchmarks from Intel. Therefore, it should be well suited for 1080p and high resolution gaming.

The power consumption should be quite similar to a dedicated Vega Mobile GPU, but due to the small form factor, smaller laptops can be built with the Kaby-Lake-G SoC. The TDP is specified at 65 Watt for the whole package including GPU, CPU and HBM2 memory.

Intel Iris Plus Graphics 640

The Intel Iris Plus Graphics 640 (GT3e) is a processor graphics card for Kaby Lake models announced in January 2017. As the successor to the Intel Iris Graphics 540 (Skylake), the Iris Plus Graphics 640 is used for 15-Watt ULV models and is equipped with 64 MB eDRAM cache. There should not be any big changes compared to the Iris Graphics 540.

The so called GT3e version of the Kaby Lake GPU still has 48 Execution Units (EUs), which can reach up to 1050 MHz depending on the model. Besides eDRAM cache, the Iris 640 can also access the system memory (2x 64 Bit DDR3L-1600/LPDDR3-1866/DDR4-2400) via processor interface.

Compared to the Iris Plus 650 from the 28-Watt models, the Iris 640 only has a slightly lower maximum clock as well as the lower TDP, so the utilization of the Turbo Boost potential should be worse.

Performance

The exact performance of the Iris Plus Graphics 640 depends on the CPU model, because maximum clock as well as the size of the L3 cache can differ a bit. The system memory (DDR3/DDR4) will influence the performance as well.

The fastest chips are high-clocked Core i7 models like the Core i7-7660U. Depending on the game, the Iris Plus 640 will probably be similar to the previous model somewhere between a dedicated GeForce 920M and GeForce 940M and is usually limited to low settings in modern games.

Features

The reworked video engine now fully supports hardware decoding of H.265/HEVC videos. Contrary to Skylake, however, Kaby Lake can now also decode H.265/HEVC Main 10 with a 10-bit color depth as well as Google's VP9 codec. The video output is possible via DP 1.2/eDP 1.3 (up to 3840 x 2160 @60 Hz), whereas HDMI is also supported in the older 1.4a standard. An HDMI 2.0 output can be added via converter from DisplayPort. The GPU can drive up to three displays simultaneously.

Power Consumption

The Iris Plus Graphics 640 is used for 15-Watt ULV processor and therefore thin notebooks and Ultrabooks.