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PSU calculator giving wrong results?

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ryantt

Member
Joined
Dec 12, 2004
I just went in to this http://outervision.com/power-supply-calculator site and type in my full system and results came that i need a 900+ power supply ...I use my kill a watt measuring tool and the max my pc is using is 398 watts and thats overclock and stress testing and gaming ...Is my kill a watt defective or the calculator showing wrong results?
 
Calculators always read ridiculously high so the PSU manufacturers get you to buy bigger more expensive items. ;)
 
To get results THAT off in the calculator, you had to mis-type a value.

Clearly, if your GPU is rated to 250W and your CPU to 95W, add 50W for fans, SSD, HDD, chipset, etc... you aren't hitting 400W. Also these are with each component running 100% of the time.
 
thanks guys i just test newegg / msi and cooler master calculator and they give me a little better results msi calculator been the closest to my actual readings recommending me a 530w psu..I just dont know why this forums recommends that psu calculator site and making people buy hi watt expensive psus
 
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We don't. We say to go there to give you an idea...not that it is or they are exact...We also spell it out for them that these calcs are high, which is why we ask for system components and give a recommendation that way.

As I said, I am betting money says you typed something in wrong to have it suggest a 900W PSU...

EDIT: Yeah, I typed in from your signature and it suggested 652W PSU (inc CPU overclock and 1.30V, 4 fans, 3 USB devices, etc). Clearly you typed something in wrong. You have a lot of nerve blaming OCF for suggesting those calc sites and "making people buy hi (sic) watt PSUs"...
 
You have a lot of nerve blaming OCF for suggesting those calc sites and "making people buy hi (sic) watt PSUs"...

Temper temper. Everybody knows blame is better to give than receive. Merry Christmas. :D
 
I took that a bit too personally, LOL! But still, we don't tell them its the bible... we tell them they over estimate for several reasons (headroom, poor quality PSUs, etc.).
 
I took that a bit too personally, LOL! But still, we don't tell them its the bible... we tell them they over estimate for several reasons (headroom, poor quality PSUs, etc.).

lol. You don't need to explain to me. I am 'we' remember? :)
 
Contact the dev. with your full specs, he seems pretty active and quick to work out any bugs. This might be something that changed with the latest update, ~6 days ago, that he's not yet aware of.
 
Iam sorry if i offend u or the forums my apologies but as u can see the link is in a sticky on this forums and because of that sticky i spend more than i need it to on a psu that's all and i don't want other people to lose money when they don't need to ..Maybe add to the sticky to spend on a kill a watt tool to have an idea how much watt u really need on a psu would be helpful..i attached a pic of the actual results of that link.. psu.jpg
 
And it will stay a sticky. As we said earlier, the calcs work good enough to give you an idea of what you need. What you posted here also changed from what you said in the first post (900+W to 860W), so something clearly changed with those entries.

As far as the KaWatt... good idea, though, if you are building a new system, how are you going to check BEFORE you order a PSU (unless you had one laying around).

Why do you have 4 tiny 60mm fans? What are those doing?

Where I think the calc has a problem is with the 980Ti and its clocks. There is over 100W difference there from 1000 Mhz to 1455Mhz. Considering its a 250W card with power limits typically 20% over (so 300W max), it is really adding a lot more wattage there than it needs to.

EDIT: Yeah, it goes from 692W to 802W when I adjust the slider. The only way that card uses 100W more is if you modify the BIOS and pour on voltage + clocks. So few people do that, so I am surprised at this result.

I would report it to them so it can be corrected.
 
30 watts less because i did not input my 3.0 2.0 usbs and another hd that iam planning to buy ...also my card out the box is 1455 on oc mode using gigabyte software which i run 24/7 ...the 4 60mm iam using them to cool some things..and about the kill a watt yes i happened to have a 750w psu laying around and iam sure many people have as well is just an option.. np iam glad u found the bug..bdw i lower the vid clock to 950 on the calculator and i got a 733w recomendation..
 
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Using EVGA's Power-Meter power supply calc, it recommended power supplies ranging from a min of 600w to a max of 750w for my system.

So the calc in the sticky is showing pretty much the same. It gives a general idea of what psu is needed. You are the human part and disect what is needed to make an inform decision of how much you need. Everybody else here will give recommendations with quality units based on what is needed and what your budget is.

Plus as an added bonus, EVGA will give you a 20% discount code for using the calc towards their psu's :thup:

No more no less ;)
 
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