NVIDIA GeForce 945M vs Intel Iris Pro Graphics 580 vs Intel HD Graphics 505

NVIDIA GeForce 945M

The NVIDIA GeForce 945M is a mid-range, DirectX 12-compatible graphics card for laptops unveiled in March 2015. It is based on Nvidia's Maxwell architecture (GM107 chip) and manufactured in 28 nm. The 945M offers 512 shaders (compared to the 640 of the GTX 950M) clocked at 928 MHz. The dedicated DDR3 graphics memory is connected with a 128 Bit bus clocked at 1000 MHz (effective 2000, 32 GB/s). 

Architecture

Compared to Kepler, Maxwell has been optimized in several details to increase power efficiency. Smaller Streaming Multiprocessors (SMM) with only 128 ALUs (Kepler: 192) and an optimized scheduler should lead to better utilization of the shaders. Nvidia promises that a Maxwell SMM with 128 ALUs can offer 90 percent of the performance of a Kepler SMX with 192 ALUs. GM107 features 5 SMMs and thus 640 shader cores, 40 TMUs and 16 ROPs (128-bit interface).

Another optimization is the massively enlarged L2 cache (GM107: 2 MB). The increased size can handle some of the memory traffic to allow for a relatively narrow memory interface without significantly reducing the performance.

GM107 supports DirectX 12 with feature level 11_0 only.

Performance

The performance of the 945M is slightly worse than the GTX 950M but clearly faster than the 940M. The DDR3 variant of the GTX 950M is about 10 percent faster for example. Therefore, it is most suited for medium details of demanding games in 2015 (see below for benchmarks).

Features

GM107 integrates the sixth generation of the PureVideo HD video engine (VP6), offering a better decoding performance for H.264 and MPEG-2 videos. Of course, VP6 supports all features of previous generations (4K support, PIP, video encoding via NVENC API). Unfortunately, HDMI 2.0 is still not supported.

Power Consumption

The power consumption of the GeForce 945M should be somewhere around 40 Watt. Therefore it is most suited for bigger laptops from 14-inch and up.

Intel Iris Pro Graphics 580

The Intel Iris Pro Graphics 580 (GT4e) is an integrated graphics unit of the Skylake generation (top version). As successors of the Iris Graphics 6200 (Broadwell), the Iris 580 can be found in some high-end quad core CPUs and offers 128 MB of dedicated eDRAM memory. Furthermore, the so-called GT4e-version features 72 Execution Units (EUs). Besides the eDRAM cache, the Iris 580 is able to access the main memory (2x 64bit DDR3L-1600 / DDR4-2133).

Compared to the Iris Graphics 550 (28 W GT3e), the Iris Pro Graphics 580 offers more EUs (72 vs. 48) and a larger eDRAM Cache (128 vs. 64 MB).

Performance

The exact performance of the Iris Graphics 580 depends on memory configuration and CPU model (different clock speeds). However, it should be clearly faster than the old Broadwell Iris Pro 6200 and may compete with a dedicated GeForce 945M. Modern games of 2015/2016 should be playable in medium settings.

Features

The revised video engine now decodes H.265/HEVC completely in hardware and thereby much more efficiently than before. Displays can be connected via DP 1.2 / eDP 1.3 (max. 3840 x 2160 @ 60 Hz), whereas HDMI is limited to the older version 1.4 (max. 3840 x 2160 @ 30 Hz). However, HDMI 2.0 can be added using a DisplayPort converter. Up to three displays can be controlled simultaneously.

Power Consumption

The Iris Graphics 580 can be found in some mobile high-end quad core processors (45 W). Therefore, they are most likely not used in thin and light laptops.

Intel HD Graphics 505

The Intel HD Graphics 505 is an integrated processor graphics unit from the Apollo Lake generation (e. g. Pentium N4200), which was announced mid 2016. The GPU can convince with low consumption figures, but the performance is only in the low-end segment and is rarely sufficient for modern games. Being the maximum configuration of the Apollo Lake GPU, the HD Graphics 505 is equipped with 18 Execution Units (EUs) running at up to 750 MHz. The technical specifications of the GPU are based on Intel's Gen9 architecture, which is also used for the more expensive Skylake series.

Due to its lack of dedicated graphics memory or eDRAM cache, the HD 505 has to access the main memory via processor (2x 64bit DDR3L-/LPDDR3-1866, LPDDR4-2400).

Performance

The HD Graphics 505 should be slightly slower than the older Core-M GPU HD Graphics 5300, so modern games (as of 2016) will rarely run smoothly even at the lowest settings.

Features

The revised video engine now decodes H.265/HEVC completely in hardware and thereby much more efficiently than before. Up to three displays can be connected via DP/eDP or HDMI (4K probably only at 30 Hz via HDMI 1.4).

Power Consumption

The TDP of the whole Pentium N4200 chip is 6 Watts by default, so the GPU is primarily used for (often passively cooled) netbooks or thin notebooks. The TDP can also be reduced to 4 Watts, but this will obviously affect the performance.