FINALLY! A smart man who knows it is good to avoid explosion prone/crappy power supplies is a refreshing change.
No kidding. There was a thread up here not too long ago with some guy trying to convince everybody he was running quad SLi GTX 295s with like 4 HD's, and overclocked quad and a slew of misc' stuff with a 600W PSU.
Me personally, I run my system with a Corsair 850W. Too much power is always better than not enough or cutting it close. The higher the load the less efficient the PSU is, not to mention the higher you stress it the faster youll kill it. Its a good rule of thumb to try and keep your system load under 75% of the PSU's output.