Intel Iris Plus Graphics 655 vs Intel Iris Xe Graphics G7 80EUs

The Intel Iris Plus Graphics 655 (GT3e) is a processor graphics card announced in September 2017. As the successor to the Intel Iris Graphics 650 (Kaby Lake), the Iris Plus Graphics 655 is used for 28-Watt Coffee Lake-U models. The biggest difference is the doubled eDRAM-cache at 128 MB. There should not be any big changes compared to the Iris Graphics 650.

The so called GT3e version of the Kaby Lake GPU still has 48 Execution Units (EUs), which can reach up to 1200 MHz (previously 1100 MHz) depending on the model. Besides eDRAM cache, the Iris 655 can also access the system memory (2x 64 Bit DDR3L-2133/DDR4-2400) via processor interface.

Compared to the Iris Plus 640 from the 15-Watt models, the Iris 655 only has a slightly higher maximum clock as well as almost twice the TDP, which allows a better utilization of the Turbo Boost potential.

Performance

The exact performance of the Iris Plus Graphics 655 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 i7-8559U. 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 655 is used for 28-Watt processor and therefore small/medium-sized notebooks.

The Intel Xe Graphics G7 80EUs (Tiger-Lake U GPU with 80 EUs) is a integrated graphics card in the mid range Tiger-Lake U CPUs (15 - 28 Watt, e.g. Core i5 11th Gen CPUs). It is using the new Xe architecture (Gen12) and should be announced later in 2020.

The performance depends on the TDP settings of the laptop and the used cooling. First informations show that the chip can be configured at 15 and 28 Watt TDP default (as the Ice Lake-U chips) and the performance should be around a dedicated GeForce MX330 in 3DMark benchmarks. For gaming we are expecting a bit worse performance due to the missing dedicated graphics memory and driver support. Compared to the older Iris Plus G4 in Ice Lake chips, the Tiger Lake GPU should be nearly twice as fast. Benchmarks with various laptops show that the 80EU version lacks about 18% behind the faster 96EU version and on par with the MX330. Compared to AMD iGPUs, the G7 80EU positions itself around the Vega 7 and Vega 8 chips (see chart below for details).

Therefore, the iGPU is still only for lowest graphical settings and low resolutions in demanding games. Some modern games like Days Gone or Cyberpunk wont run over 30 fps in minimum settings (see below).

The Tiger Lake SoCs and therefore the integrated GPU are manufactured in the modern 10nm+ (10nm Superfin) process (improved 10nm process) at Intel and therefore should offer a very good efficiency.