What Does it Technically Mean "Requires 400 watt PSU"?

[HumanJHawkins]

What I mean by this question is, some 400 watt PSUs have a single 40 amp 12v rail. Others have 2 @ 20A or even 3 @ 14A amp rails.

So, when a graphics company says they need a 400 watt PSU, do they really mean you need at least 14 amps available to the card as would actually be available from some 400 watt PSUs? Or, do they really need 25+ amps?

Thanks.

 

[clutchc]

Those are just general estimates. Not to be taken exact. More lawyer talk than anything. They have no way of knowing what other devices you have in your system that demand high +12V power.

The +12v rails' amperage capacity and total wattage for the rail(s) is most important. Next is the quality of the PSU itself. A cheap 400W PSU won't handle any where near the load that a high quality 300W PSU will. Nor for as long or as safely.