Nvidia GeForce GTX Titan X reviewed: Crushing the single-GPU market http://revealedtech.com/computer-system/nvidia-geforce-gtx-titan-x-reviewed-crushing-the-single-gpu-market/

Today, Nvidia is launching its new, ultra-high end luxury GPU, the GeForce GTX Titan X. This is the fourth GPU to carry the Titan brand, but only the second architecture to do so. When Nvidia launched the first Titan, it used a cut-down version of its workstation and HPC processor, the GK110, with just 14 of its 15 SMX units enabled. Later cards, like the Titan Black, added RAM and enabled the last SMX unit, while the dual-GPU Titan Z packed two Titan Black cores into the same silicon with mixed results.

GM200, full fat edition

The Titan X is based on Nvidia’s GM200 processor and ships with all 24 of its SMMs enabled (that’s the current term for Nvidia’s compute units). The chip has 3072 CUDA cores, and a whopping 12GB of GDDR5 memory. To those of you concerned about a GTX 970-style problem, rest assured: There are no bifurcated memory issues here.

Many of the Titan X’s specifications have landed as predicted. The card has a 384-bit memory bus, 192 texture units (TMUs), 96 render outputs (ROPS) a base clock of 1GHz, and a memory clock of ~1750MHz. Nvidia is also claiming that this GPU can overclock like gangbusters, with clock speeds of up to 1.4GHz on air cooling theoretically possible. We’ll be covering overclocking performance in a separate piece in the very near future.

Unlike the first Titan, this new card doesn’t offer full-speed double-precision floating point, but it does support the same voxel global illumination (VXGI) capabilities and improved H.265 decode capabilities that have deployed in previous GTX 900 family cards.

The first 4K single-GPU?

One of Nvidia’s major talking points for the Titan X is that this new card is designed and intended for 4K play. The way the GPU is balanced tends to bear this out. The GTX 680, released three years ago, had just 32 render outputs, which are the units responsible for the output of finished pixels that are then drawn on-screen. The GTX 780 Ti, Kepler’s full workstation implementation, increased this to 48 ROPs.

The GTX 980 increased this still further, to 64 ROPS, and now the GTX 980 has pushed it even farther — all the way to 96 render outputs. The end result of all of this pixel-pushing power is that the Titan X is meant to push 4K more effectively than any single GPU before it. Whether that’s “enough” for 4K will depend, to some extent, on what kind of image quality you consider acceptable.

Competitive positioning

If you follow the GPU market with any regularity, you’re likely aware that Nvidia has been in the driver’s seat for the past six months. AMD’s Hawaii-based R9 290 and 290X may have played merry hell with the GTX 780 family back in 2013, but Nvidia’s GTX 970 and 980 reversed that situation neatly. Given the Titan X’s price point, however, there’s only one AMD GPU that even potentially competes — the dual-GPU R9 295X2.

The AMD R9 295X2 has a massive 500W TDP, but it’s still fairly quiet thanks to its massive watercooling solution.

Dual-vs-single GPU comparisons are intrinsically tricky. First, the doubled-up card is almost always the overall winner — it’s exceptionally rare for AMD or Nvidia to have such an advantage over the other that two cards can’t outpace one.

The reason dual GPUs don’t automatically sweep such comparisons is twofold: First, not all games support more than one graphics card, which leaves the second GPU effectively sitting idle. Second, even when a game does support multiple cards, it typically takes driver optimizations to fully enable it. AMD has historically lagged behind in this department compared with Nvidia — we’ll examine how Team Red has done on this front in the next few pages, and fold the results into our overall recommendations.

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