I think this is not a serious problem if you can spend some extra money.

With about 100 USD you can easily get a serious PC case with a lot of room and a good "80+ gold" power supply of 700-750 watt.

Most of the 1080 Ti around have a TDP of 250W.

This is my config (May 2017), and as I said is very good for me because for rendering I don't leverage on CPU but on the GPU 1080 Ti.

Cases Cooler Master ATX MasterBox 5 (but yo can get a much better case)
Mb Intel 1151 MSI Z270 SLI PLUS Chipset Z270
Intel Core i7-7700K (4,20Ghz/4,50Ghz) 1151 BOX KABY LAKE
memory D4 3000 32GB C15 Corsair Ven K2
750W EVGA SuperNOVA GQ
SSD SAMSUNG 960 EVO NVMe SSD, PCIe 3.0 M.2 Typ 2280 - 500 GB
HDD int. 3,5 2TB Seagate Barracuda
Svga MSI GeForce GTX 1080 Ti Armor 11G OC Boost: 1645mhz
Cpu liquid cooler Corsair Hydro H100i v2

Marco (mkdm)