Single page Print

A quick turn at overclocking
Nvidia boasts that GTX 1080 Ti cards can reach 2000 MHz or so with some tweaking, so we decided to turn up the clocks in MSI Afterburner to see whether there was any performance left on the table in our Founders Edition card.

To start off, we ran the Unigine Heaven benchmark for 10 minutes to allow the card to get nice and toasty. After that period, the card settled on a 1759 MHz boost clock, and temperatures hovered around 84° C. As is usual for Pascal cards, Nvidia is quite modest about the boost clock range on offer with the GTX 1080 Ti.

With that baseline established, we maxed out the card's power and temperature limits and began adding a boost clock offset to the card's stock figure until the Heaven benchmark crashed or we observed other instability. At the end of that process, we achieved a stable 1974 MHz boost clock, and GPU temperatures hovered around 85° C (albeit with much higher fan speeds and more noise than at stock clocks). We didn't observe any throttling or other limits kicking in at that speed.

Once we had a core clock dialed in, we began increasing memory speeds while playing Doom with its highest-quality textures enabled and its virtual texturing page file at its maximum size. We progressively increased memory clocks and looked for artifacts or other signs of instability. After many iterations of this process, we settled on a 6048 MHz Afterburner memory clock for an effective transfer rate of 12.1 GT/s. While the card was stable at that eye-popping speed, we saw clocks begin dipping into the 1898 MHz-1936 MHz range under load. GPU-Z indicated that the card was hitting a power limit when this happened.

A 12% increase in core clocks and a roughly 10% boost in memory clock speeds is an impressive result, although we would have preferred to have some extra voltage or board power to work with so that the card could sustain both its full memory and boost clock speeds at once. We expect Nvidia's board partners will take care of this balancing act with their custom card designs.

For an idea of what that performance boost bought us, we ran the built-in benchmark for Rise of the Tomb Raider at 4K using the same test settings we used earlier in the review. At stock clocks, the GTX 1080 Ti ran the benchmark at 67 FPS on average, while our overclock pushed that figure to 73 FPS. 9% more performance at the cost of higher power draw and fan noise is nothing to sniff at.

Be ready for that extra power draw, though, because a pushed GP102 chip sucks down a lot of extra watts. We observed a total system power draw of 414W with our overclocked card running all-out, compared to 365W for stock settings. That's nothing new with overclocking, though.