This link says semi modular? XFX 650W XXX Edition 80+ Bronze Semi-Modular Power Supply https://www.amazon.co.uk/dp/B008O50WKG/ref=cm_sw_r_an_am_at_ws_gb?ie=UTF8
My mistake; I confused it with the XFX Core Edition 650W.
Well 3GB is a bit better for gaming since watch dogs has been reported to use over 2GB of VRAM with textures on ultra, but it might just be bad optimization.
Also, the Sapphire Tri-X Toxic is arguably the best R9 280X out there. No other reason really, the cards are very close to each other.
Stupid but the only thing stopping me going for it is the free watchdogs offer with the gtx and the fact everything in my build is blue! I will decide tomorrow must sleep now, cheers for all the help it's much appreciated