PC P&C make great PSUs--the issue isn't the quality of the PSU, or even the wattage. It's the fact that he's trying to OC and crossfire on 30 amps.
I'd dissagree. Quality is important if you want stable volts under load. Otherwise you'll just get BSOD's, just like having an underatted PSU.
"Or even the wattage" then you go on to say "It's the fact that he's trying to OC and crossfire on 30 amps". Erm, simple electrical, DC Volts x Amps = Wattage. And as the Voltage is constant, 12V, you can say here that wattage or amperage rating is too low.
Besides, you can tell it's a poor quality, or a questionable branded, PSU when they rate it at 430Watts when the 12V line can only handle 360W. Although technically speaking, the other lines probably supply the remaining 70Watts (5V & 3V), it's common practice for decent PSU manufactures to give the wattage of the 12V lines only - to give the buyer a real sense of what the PSU can actually handle, as all the power hungry hardware is supplied by the 12V lines, and your HDD, DVD-ROM, etc etc, are negliable in wattage. In addition, is this it's peak load (i.e. limited in time to how long it can supply that ammount of current/wattage) or is it it's contiuous rating? Very important.
Essentially, what you are trying to do is run an overclocked 6 core CPU and crossfire on 360 Watts. At full load, your original system config, with only one GFX card, would be getting too close for comfort to its limit. And if it is only it's peak load as opposed to continous rating (on the PSU that is), then your in seriously dangerous territory indeed.
Go and get that decent gear box! although, I'd prefer the analogy that the PSU is the engine - it's that important.
