Sign in with
Sign up | Sign in

Reply to this thread

Solved Forum question

Started by Rohan Fernandes | | 9 answers
Power supply usable watts
How to find out the correct usable watts of a psu? What to check for finding it?
  • By posting on this site, I confirm I am over 13 years of age and agree to abide by the site’s rules.

a b ) Power supply
a c 95 à CPUs
September 29, 2014 9:35:59 PM

millwright said:
All power supplies have a circuit breaker, if that is what you are talking about.


all have a fuse, most good ones have overcurrent protection, once tripped it will power off, then , it will reset once disconnected from mains usually.
a b ) Power supply
a b à CPUs
September 29, 2014 6:38:33 PM

All power supplies have a circuit breaker, if that is what you are talking about.
a b ) Power supply
a c 95 à CPUs
September 29, 2014 6:26:58 PM

millwright said:
I more thing.
A power supply rated for 350 has no idea it is only 350watts, so if you connect it to a computer drawing 400watts, guess what.

That power supply will put out 400 watts.
Load control how much juice the power supply puts out.

It won't be clean power.
It will be hot.
It will put out 400watts til it dies.


most decent psu's will have an overcurrent protection and the psu will shut down.
a b ) Power supply
a b à CPUs
September 29, 2014 6:51:26 AM

I more thing.
A power supply rated for 350 has no idea it is only 350watts, so if you connect it to a computer drawing 400watts, guess what.

That power supply will put out 400 watts.
Load control how much juice the power supply puts out.

It won't be clean power.
It will be hot.
It will put out 400watts til it dies.

Best solution chosen by Rohan Fernandes

a b ) Power supply
a c 95 à CPUs
September 28, 2014 11:45:25 PM

Rohan Fernandes said:
so does corsair 350W actually give 350W of usable power?


technically yes. But using 350w of a 350w PSU, its like running your car engine on the redline, something will give a lot sooner than if you take it easy. PSU's also get noisy and hot near their max load. Ideally you want to have at about 30% headroom for reliability. so if you know your system is going to top out at 350w maximum load, you'd probably want to get a 500w PSU.
September 28, 2014 10:54:10 PM

so does corsair 350W actually give 350W of usable power?
a b ) Power supply
a b à CPUs
September 28, 2014 8:53:12 PM

Pretty much the usable watts are on the label if it is a quality brand name.

If it is a non brand piece of crap. there is no way to tell, because the label is a lie.
a b ) Power supply
a c 95 à CPUs
September 28, 2014 8:47:01 PM

to be honest, the only way to truly know is to find a review of the psu where they load test it. As a general rule i stick to you cant go wrong with Antec, Corsair, seasonic or XFX. They generally don't lie about their psu specs across all their models. Obviously the cheaper models have cheaper components and may not last as long or the power may not be as clean, but they will at least produce their rated power. Some psu manufacturers (normally the cheaper ones) will blatently lie on the packaging about the wattage, and some how they get away with this.

See all answers