proper crossfireX setup

[Joseph Acot]

so I have 2x R9 280x (sapphire vapor-x and xfx) and a CX750M. it works but i read the reqments of vapor x for crossfire is a 1000W PSU. i read the minimum for xfx is 750W PSU. should I get a 1000W or more PSU so i could get the most out of my GPUs?

 

[octavecode]

you can use any online psu calculator but yeah your psu won't be enough.280x in CF would need a quality 850-900w PSU