How accurate are PSU calculators?

[Jay123]

When I was looking for a PSU I was constantly pushed towards these webites http://www.extreme.outervision.com/psucalculatorlite.jsp

In theory they are a great idea but how accurate are they?

[Dr3nz4r]

When sing some GOOD calculator its pretty accurate...

http://www.bequiet.com/en/psucalculator/expert

this one is way better then outervision shit..

[bartekxx12]

I'm not really sure, I just used them to give me a rough estimate but also made sure to check what other people use with the same or at least similar hardware.

The fact that almost everyone of these calculators gives a different value and in some cases drastically different should tell you that they can't be that accurate...

[christoi]

The outervision one seems to be fairly accurate for given the maximum power draw of the system, though the values it gives does vary by a lot from what I've seen. The recommend wattage is completely absurd in my opinion though and the same applies for the bequiet calculator Dr3nz4r recommended.

For selecting the power supply wattage, I usually recommend around 150% of the maximum power draw of the entire system - which can be approximated by adding up the TDP of each of the components. That way even under full load the system only runs at 40-60% load, which is ideal for the longevity of the unit and the quality of the output power.

[Migals]

I'd say go 500w for any base system (no gpu), the highest end of the highest end should be fine. On a card like a 660ti or so, you can problay get away with that 500w but id go 650 to be safe. If you want another card id step up to a 750w or maybe 850w. Anything more just go all out and get a ax1200i. Thats just the way I see it.

Remember stuff like fans and leds dont really matter. And unless your case is filled with hard drives, they usually don't mean much either.

[TheFaddler12]

To be honest, PSUs are very easy to get. If you are thinking about a single video card gaming machine, get a 750w. It gives you room for tons of overclocking, fans, drives, RAM and PCI-E cards. If you want a crossfire/sli, get a 850w. My Corsair AX850w is enough for two ASUS DirectCUII GTX 560s in SLI OC'd, i7-2600k @4.2 GHz, Xonar DGX and a few WD performance drives. 850w is enough for two 670s and an i5.

[killerx525]

850W is just a tad high but i'm not sure if many has ever measured how much wattage their system draws at peak load but you'll be surprised that with 2 6950 and a OCed 1090T, peak is 527W.

[Chevaishr]

Comuters draw a lot less power than what many people believe ... an ivy i5 + a 7850 +an ssd could be powered off, though not ideally, a 250 watt power supply. ( oh boy now saw that typo ... can't fix it cuz I cannot move the cusor around in mobile :( )

[Rambo]

What happens when the powersupply hits the roof? And after a year or so, how much do they degrade?

[Ghost]

What happens when the powersupply hits the roof? And after a year or so' date=' how much do they degrade?[/quote']

The capacitors can explode if you overload them, it happened to me once during overclocking.

[gareklaw]

When sing some GOOD calculator its pretty accurate... http://www.bequiet.com/en/psucalculator/expert this one is way better then outervision shit..

Thanks for that new calculator site, this one let me select my A10-5800K cpu and showed me some examples psu i could buy.

[christoi]

What happens when the powersupply hits the roof? And after a year or so' date=' how much do they degrade?[/quote']

Most decent units come with protection systems that would automatically shut down the unit if such a thing happens, though without such circuitry it can die with a bang.

Hard to say about degradation over time, though I'd expect it would be fine for a couple of years. The quality of the output power and such would slowly drop over time, but it's usually not a large problem.