Intel Iris Plus Graphics 640 vs AMD Radeon R2 (Stoney Ridge)

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.

AMD Radeon R2 (Stoney Ridge)

The AMD Radeon R2 (Stoney Ridge) is an integrated graphics adapter of the weakest mobile dual-core Stoney Ridge APUs. At its launch, it is being used in the AMD E2-9010 and probably has 128 shaders running at up to 600 MHz. The performance can vary heavily depending on the configured TDP and the system memory.

Architecture and Features

The Radeon R4 is equipped with two cores from the third GCN generation (often called GCN 1.2 or 2.0 by the press). This means it is very similar to the Tonga desktop chip and supports DirectX 12 (FL 12_0), but the graphics cores can also be accessed via Mantle, OpenGL, and OpenCL. The GPU supports the HSA 1.0 standard as well and can therefore use the connection with the CPU cores very efficiently. The technical specifications are identical to the Carrizo predecessor. 

The video unit includes the UVD 6 (Unified Video Decoder), which can decode HEVC/H.265 and 4K with support from the hardware. More details are available in our dedicated Stoney Ridge article. 

Power Consumption

Depending on the model and configured TDP (cTDP), the 28 nm chip is specified with 10 up to 15 Watts. This means it can also be used for thin and light notebooks.