Gigabyte's GTX 1060 XtremeGaming is a full custom variant of the GTX 1060, coming with a large overclock out of the box which results in a 4% performance improvement over the NVIDIA GTX 1060 Founders Edition. Compared to the RX 480, the increase is almost 10%. The more expensive GTX 1070 is 32% ahead. It's good to see that Gigabyte has overclocked the memory chips too, something that's missing from most other custom-design cards.
Gigabyte's thermal solution does an excellent job at keeping the card cool and quiet. Temperatures only reach 62°C during gaming, which should immediately raise a red flag with the question of how noise is with such low temperatures. Noise is amazing with only 28 dBA, which makes this card the quietest GTX 1060 we have ever tested, even quieter than the MSI Gaming X. The fans also include the idle-fan-off feature which stops the fans in idle and light gaming for a noise-free experience during Internet browsing and productivity. Such excellent temperatures and noise levels at the same time show that the cooler is working extremely well, which is certainly the case for the Gigabyte GTX 1060. It also looks like a perfect execution of a triple-slot cooler design, providing definite improvements over dual-slot cards in both temperatures and noise levels. Having a thicker cooler also allowed Gigabyte to build a card that's shorter than competing models, which could come in handy when your case doesn't support long graphics cards. The loss of a motherboard slot isn't that bad, and since the GTX 1060 does not support SLI, you won't miss out on any upgrade opportunities further down the road.
Gigabyte's card includes an additional two HDMI connectors near the front of the card, which are for VR headsets. Since the NVIDIA GPU cannot support that many active outputs at the same time, Gigabyte implemented a switching logic that automatically toggles between 1x DVI, 3x DP, 1x HDMI and 3x DP, 3x HDMI, depending on which monitors are connected (the switch does require a reboot, though).
Just like on all Pascal cards, power efficiency is amazing, with huge improvements over the Maxwell architecture that is already highly efficient in the first place. Gigabyte's card only uses slightly more power than the reference design, which is mostly offset by higher performance out of the box, resulting in a 3% decrease in performance per watt. Gigabyte chose to replace the 6-pin power input of the reference design with an 8-pin, something you will never make use of because the board's power limit is set to around 130 W only, so to me, the 8-pin is mostly for show to reassure potential buyers that this card will be fine for everything you throw at it, including overclocking. A higher board power limit could have helped increase out-of-the-box performance by allowing NVIDIA Boost to boost higher for longer because there is more power headroom to do so.
With a price of $300, the Gigabyte GTX 1060 Xtreme Gaming is quite expensive for a GTX 1060, which has cards starting at $240 for the 6 GB version. There's no doubt that the Gigabyte card offers a lot of additional value for the money, but I'm not sure if it's worth a $70 price increase, especially for a GTX 1060, a product where price/performance is much more important to buyers than with the GTX 1080, for example. Still, if you are in the market for a high-end GTX 1060 that ticks most of the extra-feature checkboxes, the Gigabyte GTX 1060 Xtreme Gaming is probably the best card you can buy.