Intel HD Graphics (Sandy Bridge) vs Intel Iris Graphics 6100

Intel HD Graphics (Sandy Bridge)

The Intel HD Graphics (Family) is a processor graphics card which is integrated in the cheap Celeron and Pentium model of the Sandy Bridge generation. It is similar to the Intel HD Graphics 2000 and not with the processor graphics of the older Arrandale dual-core processors (which bears the same name). 

Depending on the processor, the HD graphics offers a different base and Turbo Boost clock speed. Currently there are three different models:

• Power Saving e.g. Celeron 847: base 350MHz, Turbo 800MHz
• Celeron e.g. Celeron B810: base 650MHz, Turbo 950MHz
• Pentium e.g. Pentium B950: base 650MHz, Turbo 1100MHz

Furthermore, the slow CPU performance of some models may influence the games a lot. For example, although the GPU in the Celeron B710 differs not much from the Pentium B950, the gaming performance was clearly worse and many games were unplayable.

As the Intel HD Graphics 3000 and 2000, the processor graphics card is able to use part of the last level cache of the processor (2MB usually for the entry level CPUs). This could be seen as a small amount of very fast dedicated memory.

Altought 2x Antialiasing (AA) is supported, the chip is as fast as when rendering 4x AA. In the Unigine Valley benchmark a similar HD 3000 i7-2637M for example reached the same score with 2x AA and 4x AA.

The feature set compared to the HD Graphics 3000 is also reduced in these entry level CPUs. E.g. Intel Quick Sync (for de- and encoding of HD videos), In Tru 3D, Clear Video HD are usually deactivated.

Intel Iris Graphics 6100

The Intel Iris Graphics 6100 (GT3) is an integrated Broadwell graphics card revealed in Q1 2015. It can be found in several low-voltage SoCs (28 W TDP) such as the Core i5-5257U or i7-5557U. While Core i5 and Core i7 chips feature 48 EUs, the Core i3 version offers just 47 EUs. Depending on the specific CPU, the maximum GPU frequency varies between 1000 and 1100 MHz.

Architecture and Features

Broadwell features a GPU based on the Intel Gen8 architecture, which has been optimized in various aspects compared to the previous Gen7.5 (Haswell). Inter alia, the shader arrays called "subslice" have been reorganized and now offer 8 Execution Units (EUs) each. Three subslices form a "slice" for a total of 24 EUs. Combined with other improvements such as larger L1 caches and an optimized frontend, the integrated GPU has become faster and more efficient than its predecessor.

The Iris Graphics 6100 represents the top-end version of the Broadwell GPU family and consists of two slices with 48 EUs. Beyond that, there is also a low-end (GT1, 12 EUs), a mid-range (GT2, 24 EUs) and a high-end variant (GT3e, 48 EUs + eDRAM).

All Broadwell GPUs support OpenCL 2.0 and DirectX 12 (FL 11_1). The video engine can now decode H.265 using both fixed function hardware as well as available GPU shaders. Up to three displays can be connected via DP 1.2/eDP 1.3 (max. 3840 x 2160 @ 60 Hz) or HDMI 1.4a (max. 3840 x 2160 @ 24 Hz). HDMI 2.0, however, is not supported.

Performance

Depending on the specific CPU, the maximum GPU frequency varies between 1000 and 1100 MHz. Even though the Iris Graphics 6100 is technically identical to the HD Graphics 6000, the higher TDP (28 W instead of 15 W) leads to a better utilization of the Turbo Boost and therefore a superior performance. Overall, the Iris 6100 is about as fast as a dedicated GeForce 820M and outperforms the former Iris Graphics 5100 by 20 - 25 percent.

Older and less demanding games such as Diablo III, Counter-Strike: GO oder Dota 2 can be played fluently in 1366 x 768 pixels and high settings. More demanding titles, however, may require lower settings or won't run at a decent framerate at all.

Power Consumption

Utilizing a new 14 nm process, the Broadwell LV chips are specified at 28 W TDP and therefore suited for medium-sized ultrabooks. The TDP is flexible and can be further reduced (23 W), which has a significant impact on performance.