Not a bad psu, but highly necessary for anything less than a dual xeon server board with tri sli, and i dont even think there is a dual xeon board that does SLI out there yet. Judging just by your sig of what your planning, you could run a 750W silencer to be true about it.
One thing you may wanna take a look a the ocz Z series 1kw,the 850W has an 850W +12v rail, and the 1kw has a 1kw rail. They are 80PLUS Gold, so 90%+ efficiency at any load level(which would save you/your parents some money, the higher the wattage draw the more you will save over just an 80% unit), no longer than a standard atx switching psu, and there are modular editions.