I Think a bit of perspective is called for here.
I bought a 1055T 6 core AMD processor at £160 to render up some scenes for work in Mental Ray after my Dual Core could not cut it.(4 Hrs per render)
Got all six cores going in Mental Ray on a scene with reasonable output in 45-50 Mins.
Same Scene in Octane with higher quality in 10-15 Mins.Not allowing for the fact that the trial and error to get the right camera angles and lighting in Mental ray used to take half an hour just to set up and test,cut short the render,adjust and try again etc.
Just one card even with 224 instead of 336 cores working has saved me a hell of a load of buggering about over the last few months,even with the Beta problems in Octane.
It's like a Ferrari 458 italia driver being caught and overtaken by a Veyron.
The Driver says " Bloody salesman...He did not tell me i would not be the fastest thing on the autoban,now i'm Pissed" as he passes the VW Golfs in the slow lane.

CPU:-AMD 1055T 6 core, Motherboard:-Gigabyte 990FXA-UD3 AM3+, Gigabyte GTX 460-1GB, RAM:-8GB Kingston hyper X Genesis DDR3 1600Mhz D/Ch, Hard Disk:-500GB samsung F3 , OS:-Win7 64bit