Cheap off-brand PSUs are a bad idea. They either won't power your equipment at all, or will fail catastrophically at some point, possibly harming other components. What PSUs are you looking at for 140 euros? I know prices in Europe aren't as good as in the U.S. but that seems outrageous. I bought a quality 650W unit (Antec Earthwatts) last month for only $90. That's powering the rig in my sig. It was previously powered by a Corsair VX550 which was rock solid. I moved that unit over to my backup rig (E8400 @ 4GHz + 8800 GTS 512 volt-modded & massively o/c'd). You should be able to power an o/c'd i7 + GTX 285 on the same PSU. Just look for something that has a maximum +12V rail output of at least 40A and you'll be fine. The two aforementioned units have 47A and 41A, respectively.

Right now, prices here seem to be outrageous, but as I got a really good offer for my current system, I am kinda obliged to act ;-)Anyway, 145€ for the Corsair HX 850W. Seems like a well done PSU, and I can only hope it will cover the system. It has a single 12v rail with 70A.But what I just read on the other forum, some guy also said that my Aurora 600W should be more than enough. And it has two 12V rails, each supplying 21V/22V respectively.

Get the Corsair HX850 its the best PSU in the consumer market in my opinion and you cant go wrong with a 7 year warranty.