That psu has triple 12v rails of 18A/16A/8A so it should have enough power for that spec but doesn't leave much headroom, especially if you overclock the gpu. However, with a GTX1080 and i7 8700 I would have expected the 850w psu to be supplied as that seems to be the standard psu for the pc with your spec. The 460w psu seems to be for the i5 and GTX1060 or lower options. Personally I would want more power and would be looking at a quality 650w psu to allow for a decent upgrade (the 2080 for example is quite a bit more power hungry than the 1080).
There are some fantastic deals on Antec psu's at the moment which end around lunchtime tomorrow. The Earthwatts Pro is gold rated, semi modular, has 648w of it's 650w on a single 12v rail and has a 7 year warranty. It is made by Seasonic for Antec. The HCG Gold are fully modular, has 648w and 744w on their respective single 12v rails and have a 10 year warranty. They are also made by Seasonic and are basically a Seasonic Focus Plus Gold in a different casing.
My basket at Overclockers UK: