On my new build, my 750W PSU and one of the two 6870's arrived DOA. I have sent in the 6870 for a replacement, and the 750W for a full refund. Currently, I'm only using one 6870 - the same specs below, just with ONE 6870. With my current 550W OCZ Faility PSU, I have experienced NO problems; even when everything is on 100% load. Six hours of Skyrim, two hours of rendering, it runs perfectly smooth.
This is my build which the power supply will be powering:
i7-2600k overclocked to 4.5ghz (Hyper212+ Cooler, doesn't go over 65C under 100% load after 30 minutes)
TWO Radeon HD 6870 1GB in CrossFire
16GB Corsair DDR3 1600 RAM, high performance profile
Antec Three Hundred Illusion Case
120GB Corsair Force 3 SSD
640GB 7200RPM "generic" Western Digital drive (nothing special here)
I want to be able to power the above build, and I want to power it with clean, efficient, and good energy; not some crappy PSU which provides my expensive components with inefficient and "dirty" energy, killing the components overtime.
I also want surge protection, but that's pretty standard nowadays. My power strip has it, also. I'm always making sure.
Now, onto the PSU, here is what I NEED:
Wattage: Probably at least 750W. This build is ran fine by 550W - and another 6870 is not going to add on 200W.
Price: $70-$100. May go over $100, but not by TOO much.
Brands of favor: Corsair and OCZ. My Corsair RAM and SSD have given me absolutely ZERO issues. My 550W OCZ PSU is running amazingly well - but, my old 750W OCZ PSU failed after two years of hardcore usage. Expected; it was only $65 and I got more than enough usage out of it.
The important metric for a gaming psu is the total amperage it can deliver on the +12v leads. Not the wattage.
The OCZ Fatal1ty 750W you linked to can deliver 54a which is a bit substandard for the wattage. It should be 62w.
OCZ is ok quality. My short list of quality psu's would include Antec, Corsair, XFX, Seasonic, and PC P&C.
A quality psu will deliver it's power continuously, not just at peak. It will do so at 50c. the temperature inside a case, not 20c which is what cheap units do.
Since you're going Crossfire...This is what I would choose for your budget. It's a bit more than what you want to pay. Believe me..if you're going to pay that much for your computer components..you don't want to cheap out on the Power Supply.