[Solved] Is 750w big enough for SLI 680s?

Yes its enough provided the PSU is of good quality like the Corsair AX750

What is the rest of the system specs.

If you have an i7, 8gb (4gbx2), high end mobo, DVD-RW, and normal 7200rpm harddrive with those two gtx 680's the math equals to a recommended wattage of 770w

You want a really good 750 watt.

But my question is, if you can spend that much money on two GTX 680's, why skimp on a power supply? Thats Probabaly the worst thing to do.

I can tell you that an i7 X58 at 1.36250v and 2GTX670 at 1.2120v with +145% Power Target; full stress on Prime95 and Kombuster I am pulling from the PSU (Corsair AX860i so it has a digital output to tell me), I can draw 760w.