NVIDIA GeForce GTX 1080 Founders Edition Review

NVIDIA's next generation video card is here, the GeForce GTX 1080 Founders Edition video card based on the new Pascal architecture will be explored. We will compare it against the GeForce GTX 980 Ti and Radeon R9 Fury X in many games to find out what it is capable of.

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GeForce GTX 1080 Founders Edition

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One of the major points here naturally is the improvement in manufacturing process. We have finally broken free from the chains of 28nm and better processes are finally available. It has been a long time coming, and now with this move to a 16nm FinFET manufacturing process for Pascal great things are before us.

There is potential here, and a lot of it for future growth as the process matures even further. Just look back to how much was squeezed out of 28nm over time. Maxwell did what no one thought possible on 28nm and provide a large boost in performance and efficiency to the previous Fermi GPUs prior. If that much could be done with 28nm and we are just at the beginning of 16nm FinFET think about the potential for improvement over the lifetime of this manufacturing process. Considering the clock speeds NVIDIA is getting already with this new technology there are good things in store for this process in the future.

Instead of HBM 1 NVIDIA has co-developed GDDR5X (G5X) memory. HBM 1 has its limitations, it is currently "limited" to 4GB total capacity, something that the AMD Radeon R9 Fury and Fury X have been criticized for. HBM 1 has also had yield issues leading to higher prices and availability problems. Most of these issues should be solved with HBM 2, which allows even higher bandwidth and much higher capacities but right now HBM 2 is also having yield issues, and it just isn't ready.

Therefore NVIDIA and Micron have come up with this interim technology which extends the usefulness of GDDR5 memory by improving upon efficiency and performance. GDDR5X is a great transition to HBM 2 giving time for HBM 2 to mature. GDDR5X is a smart move, as it allows NVIDIA to use high VRAM capacities right now such as 8GB on the GTX 1080 and GTX 1070 with lower power and higher frequency resulting in double the bandwidth of GDDR5.

Pascal also moves display technology forward by supporting DisplayPort 1.4 which is currently the latest standard possible. This allows support for 4K displays at 120Hz and 5K displays at 60Hz and even 8K displays at 60Hz (using two cables.) HDMI support is improved from HDMI 2.0 on Maxwell to HDMI 2.0b on GTX 1080/1070. HEVC decode and encode is supported as well as VP9 support.

GeForce GTX 1080 Founders Edition Architecture

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The GPU codename for GeForce GTX 1080 is GP104 which consists of four GPCs, twenty Pascal Streaming Multiprocessors and eight memory controllers. In GTX 1080 you will find a dedicated raster engine and five SMs. Each SM contains 128 CUDA cores, 256KB or register capacity a 96KB shared memory unit and 48KB of L1 cache with eight texture units.

What this boils down to is that on GeForce GTX 1080 you will find 2560 CUDA Cores with a base clock of 1607MHz and a GPU Boost Clock of 1733MHz. You will find the GPU Boost Clock varies while gaming, and we will show you what we achieved while playing a game for 30 minutes of gameplay. There are 160 texture units and 64 ROPs. This provides 277.3 Gigatextures/sec and 8873 GFLOPs. GDDR5X memory runs at 10,000MHz (10GHz) on a 256-bit memory bus providing 320GB/sec of bandwidth.

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Here are the details above on the new memory, this is a big part of the GeForce GTX 1080 and 1070. 10GHz isn't even the maximum potential of this memory, it is just the starting place. Expect to see 11GHz and upwards as the technology matures. The number 15GHz has been thrown around, and that is just insane to think about memory operating at such high a frequency. While HBM comes by its performance by increasing bandwidth per pin, GDDR5X is doing it by brute clock speed force. The benefit, as we mentioned is that NVIDIA can use as much of it now as it wants, giving us 8GB of dedicated VRAM capacity on GTX 1080 and GTX 1070.

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Maxwell GPUs benefited from Delta Compression for improved performance and savings on bandwidth. Pascal also improves upon this with improved Delta Compression. 2:1 compression has been enhanced to be effective more often. A new 4:1 delta color compression mode has been added. A new 8:1 delta color compression mode combines 4:1 constant color compression of 2x2 pixel blocks with 2:1 compression of the deltas between those blocks. The improved compression plus bandwidth increase from GDDR5X provide a 1.7x effective memory bandwidth increase over GeForce GTX 980.

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HDR display support is going to be a big topic this year, especially when AMD Polaris is launched. HDR displays are coming, and they are poised to give us a whole new perspective on image quality.

The GeForce GTX 1080 is capable of 12b color (BT.2020 wide color gamut), SMPTE 2084 (Perceptual Quantization) and HDMI 2.0b and DisplayPort 1.4 for 10/12b 4K HDR. Pascal introduces new features such as 4K@60 10/12b HEVC Decode for HDR video, 4K@60 10b HEVC Encode for HDR recording or streaming, and DisplayPort 1.4 ready HDR Metadata Transport. GeForce GTX 1080 is capable of 7680x4320 @ 60Hz. It will certainly be interesting to see how AMD Polaris compares in display technology and HDR support.