Efficiency is not what the psu can give, but what it will drain from the wall outlet. Since this psu is 85% efficient, it means that it will draw only 15% more than what the pc needs, from the wall. So if your system needs 400w it will draw 460w. Efficiency is to decrease the electricity bill.
Now +12v is THE most important voltage nowadays, since most components run on it. +12 EPS, pci-e power connectors are all +12.
Take a look at the specs pic of these psus:
You will see that under the +12 of the 500w unit is actualy 432. Low yes, but also means that the psu PEAKS at 500w but it cannot run more than 432 for long time.
The 600w unit, is 504... 100w less... Can you say marketing!!!.
And finally the "700w"... 552w... So you see these psus are not so great. Stay away from them.
As i said before, and some ppl. Stay away from ocz, and plz forget Thermal take for a while. Go xfx if you can find. Also gigabyte 800w are good, their 720 superb is actually 600w but PEAKS @ 720, but 800 is 800. Xfx are THE best psus i have seen in lebanon, since we dont have seasonic/corsair/antec/silverstone..etc Inwin are not that relaiable as they tend to fail after a while, but its all luck. Thermal take we have the old models from 2004, you will see 700w with 4pin power and 1 6pin pci-e (maybe 2), but they are indeed old models. And finally coolermaster are decent. So go CM or GIG or XFX, no specific order except for xfx since they are seasonic at heart :).
And get a 2500K. What mobo did you choose? Gigabyte or msi?
