Gigabyte's GeForce GTX 1080 Xtreme Gaming comes with a nice overclock right out of the box, 1759MHz base, 1898MHz boost clock and a small bump to the VRAM frequency to 10.2GHz.  At the push of a button you can add an extra 25MHz to the GPUs clocks assuming you install the bundled GIGABYTE Xtreme Engine which also allows you to manually tweak your settings.  The Package part of the official name indicates that Gigabyte's Xtreme VR Link header panel is included with the card, you can install it in the front of your case to provide easy access to two HDMI connectors and two USB 3.0 ports for a VR headset. 

Pop on over to [H]ard|OCP to see how much more they could get out of the card as well as the effect it had on gameplay.

"GIGABYTE’s GeForce GTX 1080 Xtreme Gaming Premium Pack is one premium package of goodness. Not only have we got one of the fastest GeForce GTX 1080 video cards, but GIGABYTE has thrown in the kitchen sink in this Premium Package with enthusiast oriented gaming as the focus."

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