Computer Power Supply Question

[bryan]

I have a question regarding a computer power supply, actually more of a general question.

If a computer power supply is rated for 300 watts how much max amperage will it supply at 12 volts or 5 volts.

What is the formula for calculating this. thanks in advance.

 

[petesmc]

You can't work it out like that. On the side of the power supply it almost always gives you the rating, of how much Amps for the 5V and the 12V lines.

If it is in power, using

P = I * V to work out the Amps.

-Pete

 

[bryan]

Thanks, but then what is the purpose of the actual rating of a power supply then?

 

[Nigel Goodwin]

Thanks, but then what is the purpose of the actual rating of a power supply then?

It tells you the total rated capacity, that of all the supplies added together. The actual rating of each particular voltage is designed for the relative power requirements in a PC.