I got one of the cheap-ish OEM cooler Sapphire branded RX Vega 64 boards from a 100 unit firesale at OCUK almost 4 weeks ago (it ended up being cheaper shipped than the cheapest 1080 I could find on sale in .dk at the time).
Last night, I finally sat down and fiddled with undervolting (1050 mV across the line) and underclocking it (-1% -- effectively nothing, but enough to keep it stable) and upping the power limit (+25%) after seeing [url="https://www.reddit.com/r/Amd/comments/73ikda/rx_vega_extreme_undervolting_overclocking_and/"]this reddit post[/url], which ended up giving me almost +400 points of performance in Unigine Superposition 4K over the Turbo preset at the same wattage and +600 (+10%) over the Balanced preset.
While the card doesn't boost as high as in Turbo, it is able to consistently stay above 1500 MHz and not reach its thermal ceiling with the fan spinning at 2800 RPM (loud, but doesn't whine and can't hear it in-game when using headphones).
I'll probably get an Arctic air cooler for it at some point, but so far I'm pretty happy with it.
DD: E7200@3.16, 4GB, GT240, Solus/MATE
Dev: FX-8350, 16GB, HD6570, F26/WS
Hackintosh: Q9400, 8GB, HD4850, Sierra
HTPC: E7500, 4GB, HD6450, Solus/Kodi
Srv: PhII X4 955BE, 16GB ECC, iGP, F26/Srv
Win: email@example.com, 32GB, RX Vega 64 (air), W10Pro