Only some of OCZ's power supplies are good. The same is true with most manufacturers who have PSUs that can be recommended. For this reason, it is always about the individual units and never about brand names (this includes certain brands that shall not be mentioned yet). If there's one thing that bothers me, it's when I work hard to make a nice list of a bunch of different PSUs only to have someone else come along and say "Just get a PSU by the brand I put below", or "Just get a PSU by one of the several brands I listed below".
I don't know if anyone has noticed yet, but when I put a list together, I don't favor any particular brands. Now, there are some computer components or peripherals where a general brand name recommendation is ok, but it is never safe with PSUs. I will even include those who say things like, "Just get a Corsair", or "Just get a SeaSonic" because this doesn't enable the person to make a well-informed decision. It's more or less the blind leading the blind.
So anyway, I do recommend using the recommended list of PSUs here on OCN.
However, before you do so, which video cards are you looking at? I know you said 77xx, but can you be more specific? The difference in power requirements can be huge depending on which cards you're talking about.