Intel Iris Plus Graphics 645 vs Intel UHD Graphics (Elkhart Lake 32 EU) vs Intel UHD Graphics (Jasper Lake 24 EU)

The Intel Iris Plus Graphics 645 (GT3e) is a processor graphics card that was first seen in the Apple MacBook Pro 13 (Entry, 2019) in mid 2019. It is similar to the Iris Plus Graphics 655 in the 28 Watt CPUs.

The so called GT3e version of the Coffee-Lake GPU still has 48 Execution Units (EUs), which can reach up to 1150 MHz depending on the model. Besides eDRAM cache, the Iris 645 can also access the system memory (2x 64 Bit DDR3L-2133/DDR4-2400) via processor interface.

Performance

The exact performance of the Iris Plus Graphics 645 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 i7-8557U. Depending on the game, the Iris Plus 655 will probably be on par with a dedicated GeForce 930M or GeForce 940MX and can handle smooth gameplay in modern titles in low up to medium settings.

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 645 is used for 15-Watt processor and therefore small-sized notebooks.

The Intel UHD Graphics 24 EUs (Jasper Lake, Gen. 11) is an integrated graphics card in the Jasper Lake Celeron SoCs for laptops and small desktops. It is the mid range GPU version in the Jasper Lake series (Celeron Quad-Cores) and offers 24 of the 32 EUs (Execution Units / Shader Blocks). It offers no dedicated graphics memory and the clock rate depends on the processor model. At launch there are two Celeron models (N5100 with 6W and N5105 with 10W) clocked at 350 - 800 MHz.

Thanks to the improved architecture and more EUs, the UHD Graphics is clearly faster than the old Gemini Lake SoCs (e.g. N5000).

A special new feature of the Gen11 graphics card is the new Variable Rate Shading (VRS) support. With it game designers can decide where to spend shading time and e.g. shade object in the background or behind fog with less resolution (up to using only one source for a 4x4 block). With this technique early results show up to 1.3x performance in Unreal Engine POC and 1.2x speedup in Civ 6. Up to now VRS is only supported by the new Nvidia Turing architecture (GTX 1650 and up).

Another improved hardware piece is the integrated video de- and encoder that was improved significantly according to Intel. They did not specify any more details, but the previous generation was able to decode VP9 and H.265/HEVC in Main10 profile with 10 bit color depth using the dedicated hardware.

The Jasper Lake SoCs and therefore the integrated GPU are manufactured in the 10nm process (like Ice Lake probably) at Intel that should be comparable to the 7nm process of TSMC.