Nvidia GeForce GTX 980 Ti Review

Nvidia GeForce GTX 980 Ti 6GB Review

Manufacturer: Nvidia
UK price (as reviewed): MSRP £549 (inc VAT)
US price (as reviewed): MSRP $649 (ex Tax)

When GTX Titan X launched, it left a pretty massive gap between itself and the GTX 980 both in price and performance. This, coupled with the GTX 780 Ti, made the GTX 980 Ti practically an inevitability. Today, before AMD has even responded to GTX Titan X, Nvidia is launching the GTX 980 Ti to plug that gap, with reference boards set for availability within a week and custom boards soon after. The new card is actually far closer to the Titan X than the GTX 980, rather than arriving as a mid-way point between the two. With double precision performance on the Titan X no longer unlocked, it no longer has the high performance compute appeal that previous Titans had, so we thought Nvidia might leave more of a gap between it and the GTX 980 Ti in raw gaming horsepower. To be clear, the GTX 980 Ti doesn't dethrone GTX Titan X as the performance champion, but Titan X's lead is suddenly a lot smaller than it was when the next card down was the GTX 980.


The GTX 980 Ti utilises a slightly cut down version of the 8 billion transistor GM200 GPU. It retains its six graphics processing clusters (GPCs) and the six raster engines that come them, but loses a pair of streaming multiprocessors (SMMs), reducing its CUDA core count from 3,072 to 2,816 and the texture units from 192 to 176. As usual, there's no information on which combinations of SMMs Nvidia can disable while keeping performance the same, so the block diagram below is just for reference and not necessarily a true physical representation.


The GPU is clocked the same as it is in GTX Titan X; a round 1GHz base clock with a 1,075MHz rated boost clock and the ability to boost even higher in the right conditions. It has the same 250W power envelope too, and Nvidia is again promising tremendous overclocking potential and the ability for many cards to boost past 1.4GHz – see how we got on a little later.

The frame buffer has been halved to 6GB of GDDR5, which is still plenty. This is linked to the card via six 64-bit memory controllers for a total 384-bit bus. Combined with the standard 7GHz effective clock speed, GTX 980 Ti has the same 336GB/sec of peak memory bandwidth as the Titan X. With 16 ROPs and 512KB of L2 cache per controller, these stand at 96 and 3MB in total respectively, and rest assured that these are all fully intact with no partially disabled elements.


Essentially, the reduced SMM count and frame buffer are the only things separating the GTX 980 Ti from Titan X, and it is less than 10 percent behind the flagship card on paper. As such, Nvidia is still positioning it as a card suitable for single GPU 4K gameplay. After all, it also benefits from the Nvidia's third-generation colour compression and Maxwell's larger internal caches, both of which help to alleviate memory bandwidth bottlenecks (as explained here in our GTX 980 review), which are important at high resolutions.

As a GM2xx card, the GTX 980 Ti has full support for the Direct3D 12 API (the graphics portion of DirectX 12) all the way up to and including feature level 12_1, where the more advanced rendering techniques reside. It also supports a new feature called volume tiled resources, which extends the principle of tiled resources to volume (3D) textures like smoke, fire, fluids, clouds etc., allowing them to be rendered with greater realism.


Physically, the 267mm long, dual-slot GTX 980 Ti is a familiar sight, sporting the lovely silver and black anodised aluminium shell with green LED logo along the top – the build quality is excellent as always. It uses a vapour chamber to draw heat away from the GPU, and a metal contact plate for all of the memory chips and MOSFETS. Heat is then dissipated into a pair of heatsinks and cooled by the radial fan, which exhausts the vast majority of its air directly out of your case.


As usual, a dual-link DVI-I connection is joined by a HDMI 2.0 one and three DisplayPort 1.2 plugs, any one of which can be used to run a G-Sync monitor, which the card of course supports. Nvidia is also announcing two new capabilities for G-Sync. One is the ability to enable or disable v-sync, which affects the image when exceeding a panel's maximum refresh rate. Previously it was locked to v-sync on at all times, but is now a user choice, a move no doubt motivated by the same capability in FreeSync. The second is windowed mode; previously you had to be running in fullscreen to benefit from G-Sync. This is not something FreeSync supports.


Elsewhere on the card there are two SLI connections that support 4-way SLI, and a 6-pin/8-pin PCI-E power connection combination in line with Nvidia's other 250W TDP cards.


There are no memory chips on the rear of the card, nor is there a backplate as there was with the GTX 980. On the front, it's business as usual as well, with 12 4Gb SK Hynix memory chips surrounding the GPU, a beefy 6+2 phase power system and two headers – one for LED power and the other for fan control.