What power supply wattage should I get?

[AvidTechUser]

Hi all,

I am saving up for a new system which I hope to purchase in the next month and am a bit unsure about how big a power supply a need. I have tried different power usage calculators, but get varying recommendations.

Here are the relevant system specs for the new PC:
- Intel Core i7 6700K
- Corsair Hydro Series H80i 120mm Liquid CPU Cooler
- Graphics card: Nvidia GTX 1070
- Corsair Vengeance LPX CMK32GX4M2A2400C16 32GB (2x16GB) DDR4
- 2 SSD drives: 1TB and 500GB
- HDD: 6TB
- optical 24x SATA DVD-RW
- 4 case fans (140mm x2, 120mm x2)
- USB network adapter (always in)
- USB keyboard and mouse (keyboard is G510s, mouse is basic optical)
- Computer is usually on for about 14 hours per day, but sometimes is left on over night for downloading purposes.
- I do plug in quite a variety of USB devices, but not usually all at the same time.
- I will probably also install a PCIe 3.1 USB expansion card as well at a later stage.

The sites I have been on recommend between 500W-650W. (I was under the impression that I needed about 750W to be comfortable and prepared for the future.)

What would be your recommendation?

 

[Liviu Cojocaru]

Hi, nice setup first of all, for this I would go for a gold certified 750 PSU (EVGA,Corsair,SuperFlower or Enermax). The 750w will give you some room for an SLI if you're up to that

 

[marmiteonpizza]

OuterVision Power Supply Calculator - Good tool for working out power needed.
Just make sure you get a good quality PSU, my first had quite a lot of coil whine which was extremely annoying! A metallic whine in the background most of the time which I could never quite get used to.

 

[R-T-B]

Brand will be far more important than wattage, though I wouldn't go below 500W certainly.

EVGA, Seasonic, Super Flower, higher end Corsairs are all very good.

 

[64K]

A quality 550 watt PSU is plenty for your rig. If you're not on a tight budget you could get a higher wattage PSU. When you say "prepared for the future" does that include possibly SLI of that 1070 or possibly upgrading to a beefier GPU in the future?

 

[jboydgolfer]

One of the following but not limited to the following

Corsair
Seasonic
Evga
Nzxt
Thermaltake
Fsp
Or a like brand
Many companies have their bad products, but if you do even a cursory amount of research you'll find the proper units to purchase .

Personally I would go with 750 W or greater for the bill that you have listed

 

[EarthDog]

If you are not going to SLI a QUALITY 500W PSU is PLENTY for any single gpu along with overclocking both cpu and gpu. Youd be hard pressed to break 350W fully overclocked with a single 1070. I suggest evga 500B. Anything more than that when you will not use multiple gpus is a waste of money.

If you may SLI that 1070, go for 650W. I suggest evga supernova g2 650w. Anything more than that is also wasting money for your setup.

A 1070 is a 150W card stock. With power limits, fully overclocked it's not going to break 200W (likely less... 175W). So let's say you sli and overclock that is 400W out of the card. The cpu overclocked on ambient cooling won't break 150w. 400W + 150W = 550w. A 650W is plenty as those values are inflated. In my review, with a stock 6700k but fully overclocked 1070, I hit 294W AT THE WALL.

 

[AvidTechUser]

Thanks for the replies so far...

I do not (currently) intend to go SLI.

What I meant by "for the future" was more directed at a GPU upgrade.

As for the brand: I am leaning toward the EVGA SuperNOVA G2 Gold 650W Power Supply, but for around $10 more I could get the 750W version, so maybe I should go with that?

 

[Liviu Cojocaru]

Thanks for the replies so far...

I do not (currently) intend to go SLI.

What I meant by "for the future" was more directed at a GPU upgrade.

As for the brand: I am leaning toward the EVGA SuperNOVA G2 Gold 650W Power Supply, but for around $10 more I could get the 750W version, so maybe I should go with that?

I would say go for the 750w one for just another 10 bucks it's pointless to get the 650w

 

[Ebo]

Thanks for the replies so far...

I do not (currently) intend to go SLI.

What I meant by "for the future" was more directed at a GPU upgrade.

As for the brand: I am leaning toward the EVGA SuperNOVA G2 Gold 650W Power Supply, but for around $10 more I could get the 750W version, so maybe I should go with that?

If the difference is only 10 dollars, I would go for the bigger one.

 

[AvidTechUser]

Yeah I agree I might as well spend $10 more for the bigger one. But is the make/model a good choice?

 

[Liviu Cojocaru]

Yeah I agree I might as well spend $10 more for the bigger one. But is the make/model a good choice?

Yes EVGA is a great PSU brand as well as a VGA

 

[EarthDog]

I would say go for the 750w one for just another 10 bucks it's pointless to get the 650w

Why spend $10 more dollars if you dont have to??? You are going to use 300W of a 750W psu. Out of the efficiency curve (like it matters, but... it's massive overkill for NO reason at all).

Why not get the osu I suggested (evga 500b) and spend even less? For the future...think... power use is overall going DOWN guys...

There is ZERO point to go over 500W here people unless you have money burning a hole in your pocket.

 

[Liviu Cojocaru]

Why spend $10 more dollars if you dont have to???

Why not get the osu I suggested (evga 500b) and spend even less?

There is ZERO point to go over 500W here people unless you have money burning a hole in your pocket.

A PSU is smth that you don't replace that often...and who knows what you want to do in the future...so yes I say for 10$ more 750w is a better investment

 

[EarthDog]

Disagree strongly. 650W is already overkill for one card, just fine for 2!!! Why spend $10 more. It makes ZERO sense to do that...ZERO.

 

[Liviu Cojocaru]

Disagree strongly. 650W is already overkill for one card, just fine for 2!!! Why spend $10 more. It makes ZERO sense to do that...ZERO.

Wrong, the less you stress the PSU the more efficiency you get from it...so 500w in my opinion wouldn't be a good choice...

 

[EarthDog]

With respect, you have no idea what you are talking about. Efficiency curves on QUALITY PSUs are relatively flat, past say10-20% load. You do know that the 80 plus rating sets tiers at specific loads right?
https://en.m.wikipedia.org/wiki/80_Plus

Here is efficiency rating for 650g2 and 750g2. If he is pulling 300W, the difference isn't even 1%. You will only make that $10 up if you were at full load 24/7 365...

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story3&reid=429

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story3&reid=380


Would you look at that.... the same exact efficiency!!!!



D9nt spend the extra $10 OP.. seriously. The reasoning you are hearing is off the wall.

 

[FYFI13]

Take a look at my system specs Our system power would be about the same and my 500W PSU not even getting warm. 650W PSU is overkill, 750W - nuts.

 

[R-T-B]

Wrong, the less you stress the PSU the more efficiency you get from it...so 500w in my opinion wouldn't be a good choice...

It's actaully a lot more complicated than that. As a massive generalization, most units efficiencies peak at the 50% mark, roughly.

At any rate, listen to Earthdog. He isn't some newb at this.

 

[Liviu Cojocaru]

I won't go further into this as I may be wrong (or not), I've just stated my opinion...he will choose as he pleases

 

[R-T-B]

I won't go further into this as I may be wrong (or not), I've just stated my opinion...he will choose as he pleases

Well either way, 10 bucks isn't anything anyone should get upset over, so don't fret it.

You can't really go wrong with any of these options, one is just the "perfect fit" IMO.

 

[Ferrum Master]

Instead of bitching around about ten bucks you could also bring up noise factor.

Zero RPM mode at low loads may be important if you seek for silent system builts.

 

[EarthDog]

And for giggles... here is the 500b. Because it's bronze rated, efficiency is of course a couple % lower, but again, the meager cost differences to run it (a couple bucks /year) over the gold won't get it close to the cost of the 650 g2.

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story3&reid=351

OR get evga 550w g2. Gold rated, plenty of wattage and efficiency for silent operation.

Edit: yes, none are a bad choice... all will be fine. It's just getting the right piece in both, current/future needs capacity wise, efficiency, and noise. If FYF's cheap arse cx500 isn't getting warm, no way in heck you will hear the 500b, and especially the 550 g2.

Edit2: wrong opinions can cost people money. In this case, a 500b is $45, while a 550g2 is $85 and a 750g2 is $112... $67!!!). It's our job to inform the users with FACTS so they can make an informed decision.

 

[AhokZYashA]

a good 500W PSU is plenty for that build,
a seasonic G550 is a good choice if its available
an RM550 is also good

 

[Bill_Bright]

Wrong, the less you stress the PSU the more efficiency you get from it...

Sorry, but as EarthDog noted, that is incorrect - AT LEAST when it comes to quality 80 PLUS Certified PSUs.

80 PLUS Certified PSUs are required to achieve high efficiency (80% or greater) across the full range of expected loads. So as long as you don't exceed the wattage capability of the supply, the efficiency will remain flat (± 2 - 3%) and no less than 80% (or higher, depending on rating - Standard, Bronze, Gold, etc.).

Note that does not mean you must buy a 80 PLUS Certified PSU to achieve those high efficiencies and "flat" efficiency curves. That is, PSU makers can certainly design a top notch PSU but not submit it to Plug Load Solutions for testing and certification. But the fact of the matter is, the 80 PLUS Certification program is so well managed and accepted by us consumers that we now expect and demand to see the 80 PLUS logo. So manufactures know it would be a death blow (in terms of marketing and sales) if they did not submit the supply for testing and certification. And the 80 PLUS certification program is so widely accepted by consumers and the PSU industry itself as the de facto benchmark representative/standard for efficiency, consumers can pretty much assume if no 80 PLUS logo is present, the supply has lousy efficiency ratings.

In Liviu Cojocaru's defense, basic power supplies, by their very nature, are very inefficient electronic devices with typical "peak" efficiency ratings ~70%. So 30 watts out of every 100 watts pulled from the wall is wasted in the form of heat! And those supplies tend to reach those peak efficiencies at just one point (sometimes two) along the entire load range to form a "bell" shaped efficiency curve instead of the desired (for computers) flat curve. And this "bell" shaped curve is actually just fine for devices that present a fairly constant load on their supplies (a monitor, for example), as long as the designers match that load to the "peak" efficiency load point (the top of the "bell") of the supply.

Computers, however, present a constantly varying load from near 0% at idle up to 100% when maxed out. So for computers, the desire is for PSUs with "flat" efficiency curves.

So Liviu is technically correct when talking about cheap, generic, basic power supplies. But we don't recommend the use of cheap, generic basic PSUs around here!

My choice for this build would be a quality 550W supply and I really like and the EVGA 550W G2 Gold supply I have in this system and would recommend it.