Whats the difference?

[maximan1]

I mean if all PSUs do is power the computer what is the big deal with the $50 ones? I mean they're just like any other PSU just maybe a little bigger or smaller. Right?
Help me here

[AKA_RA]

theres a huge differance. would you spend a lot on every other part just to buy a cheap unreliable power supply that can easily fry all your shiney new parts to hell? a big factor on what power supply fits you best is the demands of your system. such as how much power you need, what kind of connectors you need, etc. besides, you rarely find things like multiple 12v rails or active PFC on cheap power supplies. And you need to be careful about researching a power supply before buying. I've heard some pretty bad horror stories about power supplies from certain companies. Things like them frying parts, or even catching fire.

[Omega]

Lets say you spend 3,000$ on a bunch of awesome, top-shelf parts, but 50$ on a PSU. That PSU runs a very high chance of turning that 3,000$ dream machine into a box of burned Printed Circuit Boards and Silicon chips.

[AKA_RA]

exactly my point. can anyone say, "$3000 paper weight?"

[Cevinzol]

A big thing with power supplies is their efficiency.
Look up any PSU spec sheet and find its efficiency rating. The higher the rating the more electricity actually goes to your computer. The ramainder is wasted (as heat).
Expensive PSU's should have higher effeciency ratings

Example: a 400W PSU with 75% effeciency only provides 300W power to your comp. (400 X 0.75=300) the other 100W become heat in your machine (hence why PSU's have fans)

[Omega]

A big thing with power supplies is their efficiency.
Look up any PSU spec sheet and find its efficiency rating. The higher the rating the more electricity actually goes to your computer. The ramainder is wasted (as heat).
Expensive PSU's should have higher effeciency ratings

Example: a 400W PSU with 75% effeciency only provides 300W power to your comp. (400 X 0.75=300) the other 100W become heat in your machine (hence why PSU's have fans)

So i am geussing that my "480w" PSU that actually gives me 430w is pretty damned good? =D

[archmaille]

As far as I know that is not how efficiency works. Efficiency in a PSU should refer to how much power it draws out of the wall.

here's a little reference chart from PC Power and Coolings website on efficiency ratings.

Model--------------Efficiency @ 550W----Input Power @ 550W
Turbo-Cool 850 SSI---------81.9%------------672W
Antec True Power 550-------73.8%------------745W

For the same output power, the Turbo-Cool 850 uses 73W less input power.

[archmaille]

So i am geussing that my "480w" PSU that actually gives me 430w is pretty damned good? =D

I would say no! That means one of two things, either A) your system only requires 430w so it doesn't provide anymore because you don't need it or B) your PSU manufacturer hyped up the power ratings to a level that your PSU really does not perform at.... or well it DOES perform at the rated wattage if you've got an inside case temp of 20degrees celcius.

[busandave]

so I have a question what does everyone think of the xion sli 600w atx 12v version 2.0 I am upgrading the graphics cards and need a new power supply

[simon275]

Ive read a review or two the power drop on the different rails doesn't seem to bad when under heavy use. It depends what graphics card you are putting in though and how many periaphals are in your PC like usb powered coffee warmers and 12 HDD's. But 600w should be sufficent for your needs.