Power Supply Calculator Figures Out What Size To Buy

Not only is the info not current, as other commenters have pointed out, but there is no differentiation between pata and sata hard drives and the results from the NewEgg calculator come out consistently higher than any other PSU calculator I have seen on the internet. Even with other PSU calcs that allow me to put in a number of USB devices and other options, I get a results 200-400 watts lower than what Newegg tells me I should get.

In fact, it tells me my core machine I built last year should have a 700+w PSU and that's without taking USB peripherals into account. Well, I'm running that system with a 500W PSU and not having any issues and I've got at least 5 USB devices attached that draw power.

It also tells me if I add in another Nvidia 9800GTX video card I would need at least a 1000w PSU, essentially an increase of 250w just for one video card.

It's like they compiled their data from scouring forums for comments of 15 year old PC gamers instead of relying on simple science.

This is the first time I've been truly disappointed in NewEgg. Can't win em all, I guess.

spittingangels

@mcdavey: +1 for eXtreme PSU Calc -- it is kept up to date quite nicely. The Newegg calc is pretty out of date.

From reading around:
For a single GPU system without too many hard drives, 500-600W is probably enough. For dual GPUs, shoot for 750W. Quad-SLI and lots of peripherals needs a 1000W.

The best manufacturers around are Corsair, PC Power & Cooling, BFG, and Antec. There are some other companies that make decent ones but also have worse products and some companies just make crappy PSUs outright.

i always use antecs calculator because it accounts for so much stuff. antec.com

the feature is pretty old but very useful. thanks!

There's also way more to a PSU than how many watts you get. How many 12-volt rails it contains is also a necessary consideration.

shadydentist

Agree with everyone else, my first thought was woefully outdated.

mobiusuk

Actually these calculator are not good. It's good to get some sort of idea, but it stops there.
Because it's the Amps that powers up your computer not Watts. They are efficient PSU's that offer more Amps per Watts, and some are not at all. PSU is the heart of the system, and a good quality should always be the one to pick.

Also, this calculator is totally out-dated.

GoodBytes

Nice idea, but it seems to be missing a lot of components. No i7 CPUs and no nvidia 200+ cards. Bummer.

The tool is pretty out of date. It's missing a lot of the newer components such as the Phenom series, the Radeon HD 3000 series and up and DDR3 RAM.
Not exactly very useful for building a computer nowadays unless you're building a really low end one.

Seems a little outdated. No Intel i7 or AMD Phenom / Phenom II CPUs listed.

Plus the GFX list stops at ATI X / nVidia 8 series, which is about 3 generations back.

No DDR3 either, and only goes up to 2GB.

Good idea though, props to Newegg.

Bennal

Waaaaay Outdated

jonthomasdesigns

741 watts for that?! That seems really high to me.

On a related note, this site has a more in depth PSU calculator.

http://extreme.outervision.com/PSUEngine

@WaylenEscared: That site is far better, thanks for the link.

@VenomIreland: Also, this is kind of outdated, doesn't even have the 9xxx series from nVidia and where did my star go?

http://www.extreme.outervision.com/psucalculatorlite.jsp i like this power supply calculator. much more advanced option wise and actually has everything you need.

mcdavey

Seems alright if you plan on doing a general-use computer. The lack of any Phenom love hurts though.

tok3ninja; is the best non-star commenter

@mcdavey: Epic Fail - very outdated..

This page hasn't been updated in ages... just look at the hardware choices, the latest stuff is about 2 years old

JacksonDane

@agraek:

no the links arnt i see links to articles not the products

Philip Marquis

I find the best way is get a benchmark of maximum power usage under full load of all major parts (GPU, CPU) and add 100 watts or so for headroom.

@agraek: i agree that there is no ddr3 ram, etc. the 2gb ram is per stick though.

mcdavey

@agraek: outdated is right. i went and tried this a year ago, and they had yet to add the ATI 4000 series vid cards or any of the newest Core 2's at the time. This one is updated more often and usually more accurate. http://extreme.outervision.com/psucalculatorlite.jsp

WaylenEscared

The link is at the bottom of the post...

Also, this seems to be outdated. There is no option for more than 2gb of ram, the highest it has is ddr2 and it doesn't have the newest generation of video cards from ati or nvidia.

Fail.

agraek

why are there no links to stuff anymore? i don't like having to good stuff -.-'

Philip Marquis

Seriously, the calculator says 40W per harddrive. That's just ridiculous. Just to give you guys an idea:
http://www.wdc.com/en/products/products.asp?driveid=311

Mighty72

there is no GTX280, 285, corei7 1366, or ddr3 ram!!!

@rup3t: Yeah, it was great to check it out and have nothing there actually work for my machine but the hdd/dvd/mb (and presumably the mb is wrong too).

@TheFu: One example does not make your stance very strong, though I do agree with your general idea.

Most home users need around 350 watts, but not because that's what their peak will be. PSUs are designed with that number as their absolute maximum. Its like your car's top speed. Most will never push the boundaries, but no one would buy a car with a top speed of 70. Why?

Because a car that CAN go 120 will be more efficient at lower speeds than a car running at is maximum.

If you compare two PSUs rated at 350 watts and 500 watts, and look at the overall efficiency while running a system that requires on average 300 watts, the 500 watt PSU will run cooler, quieter, and use less energy (generally. This is not a blanket statement).

For that reason, anyone looking to run a setup with dual GPUs (huge energy pigs) and a fast processor with a few drives/fans/RAM dimms would want more than a 500 watt PSU, not because their peak will be higher than 500 watts, but because they want a PSU that will run well and for longer.

Most people will be shocked when they plug a Kill-a-watt in for their PC and see 150W used peak. Most normal desktops use 30-50W.

Good thing we're being sold 750W power supplies if you have 2 SLI graphics cards, huh?
I've not used a high end graphics card, but I have run 4 disks, DVD, multiple NICs, nVidia 6600, C2D, 8GB RAM and TV tuner card with a 350W power supply very happily for years.

There is a difference between peak and RMS use and I'm not suggesting anyone get less than 300W, but anything over 500W really needs to be sanity checked. Seriously.

Buying an expensive power supply doesn't mean anything. I've had cheapo-included-with-case PS last longer than $120 name brand version which died 1 week after the warranty was up.

TheFu

@Posco Grubb: Ya, that one has a "pro" version that will do how much power you'll need per rail, which is just as if not more important.

watcher_b

Not only is it outdated it also increases the required PSU sizes by 40%-60% on the two configurations I entered compared to other trusted calculators.

Axekick

This one seems to be a bit outdated, the newest graphics card they have is the GeForce 8800GTS, which is a few years old now. There's one here http://extreme.outervision.com/psucalculatorlite.jsp that gets updated quite often.

The calculator doesn't even have Phenom processors. The ATI cards go up 2900 and nvidia to 8800. Seems out of date to me.

ethanthekiwi

@whereisian: I want to be able to "thumbs up" this comment.

In December, I put together my current system (i7 920, Radeon 4870, 4xHDD, 2xBluRay/DVD) and having read articles at SPCR, came to the conclusion that even a 400W 80+ PSU would do the trick. I borrowed a power meter a few weeks ago and confirmed this: it didn't even get close to 300W.

The awful calculator recommended by this post doesn't allow for modern hardware but the nearest options suggested well over 800W! If I'd been in the market for el cheapo misrated PSUs, this might be right, but efficiency is important to me.

What really needs to be stated is that buying an overrated PSU is a bad idea because PSUs are most efficient at around 60-80% of maximum rating and quite inefficient below 25% of maximum rating, so when you use a 750W PSU to power a PC typically using 100-150W, there's a lot of energy wasted as heat.

The one thing this post gets right is "buy quality—don't cheap out": spend a little more on an efficient PSU and less on your electricity bills and replacements. And buy one that provides what you actually need, not what you think will make your über-rig seem more cool.

it's handy for people who are very unsure of what they need. I find most people recommend a lot more power than necessary, but I suppose that's the better safe than sorry ideology.

My setup rated at 357watts, which seems pretty close to me. I don't have a kill-a-watt to verify unfortunately. Gotta love low-power onboard graphics.

m-unit

@Posco Grubb:
I used that PSU Estimator, Newegg knows the more watts, the more money they make.

SmartedPander

Horrible calculator, no mentions of lots of ancillary items and reads far too high.

I have tested the wattage of my system and the calculator gave a reading 150-200 Watts higher than what it uses under full load when heavily OC'ed with fans, lights and a water cooling pump running as well.

There are other far better ones out there.

Lagertop

Newegg's calculator doesn't give you very many options, and is hopelessly outdated (it doesn't even include Phenom CPUs, ferchrissakes). I very much prefer this one.

HeartBurnKid: Agent of R.O.A.C.H.

@watcher_b: The link: http://extreme.outervision.com/psucalculatorlite.jsp

I use a 500W for my rig, and that tells me I need a 625 :(

I suppose considering that it's been working for a few years now, it my PSU can't be too wrong.

I just went through the pain of buying a power supply. I found that various different calculators would vary in their estimates by as much as 200W.

I highly recommend reading through the Power Supply Fundamentals article at silentpcreview.com.

Many of the calculators are put out by PS mfgs, so take the estimates with a grain of salt. Basically, it boils down to efficiency and build quality.

I also recommend the thread "How much will a 300w power supply run?". It's particularly interesting as most of the posts are from the era of very power hungry components.

For me, I just ordered a 400W Corsair PSU to power an AMD 5050e on a Gigabit 780G mobo with 4GB of RAM with 4 HDD (and possibly a capture card in the future).

whereisian

I've always liked Newegg and their little helpers. I bought an Antec PSU from them recently and I've been happy with it.

I disagree that this is a good PSU calculator. With so many psu intensive elements in computers now a days, a calculator that figures out how many amps are needed on each rail is so stinking important.

And so far the only calculator that I've seen that includes that is the extreme.outervision one, but at cost (it is like $2).

watcher_b

The antec tool found at http://www.antec.outervision.com/ is a much better tool

@WaylenEscared: Excellent link. This is what I like about Lifehacker, the good comments.

CGA

@TehNomad:I've also had good luck with SeaSonic supplies. I started using them a few years back when they were one of the only high-efficiency PS makers on the market. Built several systems using them, and haven't had any problems.

I'm disappointed they don't list the ATi 48x0 series yet...

DvBoard

OMG worthless calc, doesnt have i7 neither newer video cards, this is useful 3 years ago maybe

douglatins

@UnderLoK: It's the dual graphics card there that gets it up to 741.

@TheFu:
120 $ PSU is not an expensive PSU, nor woulc I consider it anything more than a cheap-o supply, maybe if it was in 250 $ range would it be a brand name supply, how many years did your warranty last?

Also, if you spend more money you can get a more efficient power supply, which your electric bill will thank you for, as well as the environment (if you are into that).

SpartanFry

The calculator serves no use; all the hardware selection are at least a generation behind the current ones.

thexile

I'm sorry, but that's a horrible tip. This one doesn't seem updated even for current midrange PC parts, and it overstates the wattage needed to the point of being grotesque.

Holy shit, I can't believe this is featured on lifehacker. It's just that terrible. I recommend this one instead:
http://www.extreme.outervision.com/psucalculatorlite.jsp

It has support for new parts, and the recommendation more closely resembles what you actually need for a PC in my own experience.

Melonfodder

I like this idea, but it is out of date. The newest graphics card is that 8800GTS. Come on newegg, maintain your html

no phenom x4, or ati 4800 series...

but hey, pay attention...it's SERIOUSLY out-dated.

No support for Phenom processors?

daybringer

@TehNomad: Yeah, the majority of those are from the same OEM manufacturer. Seasonic makes Corsair and BFG power supplies. PC Power and Cooling used to be the best but they have gone down in quality in recent years.

mrwumasta

@TheFu: Wrong, it's much better to get a power supply that is rated 80-plus efficiency. This means it runs cooler, which is the number one reason for power supply failure.

Also a good manufacturer will include a circuit protection function to keep your components from blowing out if your power supply goes. Every time I build a computer for someone I always demand a good power supply, because without a decent foundation you could potentially lose everything.

mrwumasta

http://www.corsair.com/psufinder/default.aspx

This is a much better calculator than the one listed. 741W is way too high for the components listed. I have 4 drives, 2x9800 gtxs, phenom 2, DVD-RW, 4 GB Ram, multiple fans with a large controller unit and I only run a 520W corsair.

As long as it's from a decent company you should be good with a smaller size. My 520 actually can produce around 670-700W when it needs it.

mrwumasta