this. person is correct
as only a fool would allow the vegas to pull more then 200 watts a card.
so if the 4 cards are 200 watts each it means your psu can work just fine.
although I would try to keep each card under 175 watts
go to this thread talk to r0mi and soothaa
https://bitcointalksearch.org/topic/any-word-on-amd-vega-hash-rates-2002025
My cards are currently pulling about 210W each never done bios modding before so im waiting till I build my new pc and I can try with one card while the rest continue mining.
The PSU claims to be able to deliver 1000W constant so should be fine to power 3x Vegas, I've got another PSU for the last,
My question is is it safe to use one PCIe cable to power Vega cards ( using both 6+2 the cable has for one card ) cables are double the thickness as the ones that came with the smaller PSU.