Well I wanted to stay protected for SLI in futrue perhaps. So am I good!?
actually you can tri or quad SLI with that PSU. the 670s don't draw much power, under 175 watts. the "worse" thing you did was pay for a gold rated PSU when the load you have on it would give you the efficiency of a silver or bronze rated.
here. PSUs take a huge nose dive in efficiency under 20% load:
now fortunately for you it won't be as bad because that PSU performs better on low loads than most others.Corsair AX850 850 WEfficiency at Low Loads
In the next tests, we measure the efficiency of AX850 at loads much lower than 20% of its maximum rated load (the lowest load that the 80 Plus Standard measures). The loads that we dial are (approximately) 40, 65 and 90W. This is important for scenarios in which a typical office PC is in idle with power saving turned on.
Efficiency with 41W load is nothing to write home about. However the situation dramatically changes with over 66W load and efficiency gets a significant boost as it easily passes the 80% mark.
your lowest efficiency is 76.29% at 41-54 watts; and then 82% @ 65 - 80 watts that is pretty much where you will be idling at the same efficiency of a bronze PSU.
when you go above 90 watts, a bit of a load, then having a gold rated PSU will pay off.
so get another 670 play a lot under 100% load for your gpus and cpu to get over 350 watts and be happy with a very efficient PSU