The NVIDIA GeForce GTX 980M is a 28 nm DirectX 11 graphics card for high-end notebooks. It was introduced in Fall of 2014 and is based on the Maxwell GM204 architecture. The clock rates specified by Nvidia are 1038 MHz (+ Boost) for the GPU and 1250 MHz (5000 MHz effective) for the up to 8 GB of GDDR5 memory.
Architecture
Just like the mid-range GM107 chip (GeForce GTX 860M), the GM204 is also based on Nvidia's new Maxwell architecture, which replaces the previous Kepler generation. Among other changes, Nvidia have restructured the streaming multi processors (SMM) in order to increase workload and efficiency. Now each SMM contains only 128 shader units and 8 TMUs, which is noticeably less than an equivalent Kepler GPU. The GM204 features four GPCs, and each consists of four SMMs. But, in the GeForce GTX 980M, Nvidia have deactivated 4 of 16 SMMs. As a result, only 1536 shader ALUs and 96 TMUs are active. In addition, there are 64 ROPs in four clusters with 16 units each.
The memory interface has a bandwidth of 256-bits (4x 64 bit). Thanks to an improved compression algorithm, the connection to the GDDR5 memory should be significantly more efficient per MHz. Furthermore, the L1 (96 KB per SMM) and L2 caches (2 MB) have been significantly increased to lower the needed bandwidth.
Although the GM107 and the GM204 both belong to the Maxwell generation, the newer and larger GM204 has several additional features and changes. Aside from the improved polymorphic engine in the SSMs, it is also the first Nvidia chip to support DirectX 12 Feature Level 12_1.
Performance
Thanks to the increased efficiency, the GeForce GTX 980M performs significantly faster than the former top model, the GTX 880M. Consequently, it is the fastest mobile graphics card as of 2014. According to our benchmarks, it is about 40 - 50 percent faster depending on the scenario. Thus, the GTX 980M is powerful enough to run even the most demanding games with highest details and FullHD resolution. Additional visual features like anti-aliasing and anisotropic filtering are also not a problem for this card as of 2014.
