NVIDIA GeForce 840M vs Intel HD Graphics 5500

NVIDIA GeForce 840M

The NVIDIA GeForce 840M is a mid-range DirectX 12-compatible graphics card for laptops unveiled in March 2014. It is one of the first cards based on Nvidia's new Maxwell architecture (GM108 chip), but is still manufactured in 28 nm. The 840M offers 384 shader units clocked at 1029 MHz (+ Boost) as well as 2 GB of DDR3 memory (64 bit, 2000 MHz effective).

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. GM108 features 3 SMMs and thus 384 shader cores, 24 TMUs and 8 ROPs (64-bit interface).

Another optimization is the massively enlarged L2 cache. The larger size can process some of the memory traffic to allow for a relatively narrow memory interface without significantly reducing performance.

Similar to Fermi and Kepler, the GM107/GM108 support DirectX 12 with feature level 11_0 only.

Performance

According to our benchmarks, the GeForce 840M is about 30 percent faster than the old GT 740M and just slightly behind a GeForce GT 750M (DDR3 version). Many games of 2013/2014 can be played fluently in WXGA resolution (1366 x 768) and medium or high detail settings. However, very demanding games such as Crysis 3 or Battlefield 4 will require lower resolutions and/or details.

Features

GM108 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 840M should be about 30 Watts or lower. Therefore, the GPU is best suited for laptops 13 - 14 inches in size and above. The 800M series also supports Optimus to automatically switch between an integrated graphics card and the Nvidia GPU.

Intel HD Graphics 5500

The Intel HD Graphics 5500 (GT2) is an integrated Broadwell graphics card revealed in Q1 2015. It can be found in several ULV SoCs (15 W TDP) such as the Core i5-5200U or i7-5600U. While Core i5 and Core i7 chips feature 24 EUs, the Core i3 version offers just 23 EUs. Depending on the specific CPU, the maximum GPU frequency varies between 850 and 950 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 HD Graphics 5500 represents the mid-range version of the Broadwell GPU family and consists of one slice with 24 EUs. Beyond that, there is also a low-end variant (GT1, 12 EUs) as well as higher-end models (GT3/GT3e + eDRAM, 48 EUs).

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 850 and 950 MHz. Due to the low TDP, however, the average clock in 3D applications will be somewhat lower.

Equipped with fast dual-channel memory, the HD Graphics 5500 outperforms the HD Graphics 4400 (Haswell, 20 EUs) by 20 - 25 percent and also beats the HD Graphics 5000 (Haswell, 40 EUs). However, even a low-end dedicated GeForce 820M ist about 10 - 30 percent faster than the HD 5500. Games as of 2014/2015 will usually run fluently only at (very) low settings.

Power Consumption

Utilizing a new 14 nm process, the Broadwell ULV chips are specified at just 15 W TDP and therefore suited for thin ultrabooks. The TDP is flexible and can be further reduced (7.5 or 10 W), which has a significant impact on performance.