GTX 1080 Sli

Toggle sidebar Toggle sidebar
navigation2015

navigation2015

Distinguished
Jan 16, 2016
50
1
18,535
Hello,

My PC is i7 4790k, 16gb ddr3 ram, Z97 Asus MB, Corsair H100i water cooling. 2 140 mm fans on front and one on the back. I want to install 2 gtx 1080's Sli and I'm wondering is a 1000 watt PSU enough for my system
 
Sort by date Sort by votes
turkey3_scratch

turkey3_scratch

Expert
Ambassador
Jul 15, 2014
22,627
8
60,960
What PSU model is it? Your system with two 1080s, fully overclocked GPUs + CPU, under full load, is about 615W according to my head. Without overclocking, full throttle is about 450-475W. Gaming load with overclocking is more like 540W. Gaming load without overclocking is more like 400-425W.
 
Upvote 0 Downvote
17seconds

17seconds

Champion
Jul 27, 2010
10,584
4
51,965
Here is Guru3D's power supply recommendation:

•GeForce GTX 1080 - On your average system the card we recommend a 550 Watts power supply unit.
•GeForce GTX 1080 SLI - On your average system the cards we recommend a 750 Watts power supply unit.

If you are going to overclock your GPU or processor, then we do recommend you purchase something with some more stamina.
http://www.guru3d.com/articles_pages/asus_rog_strix_geforce_gtx_1080_review,8.html
 
Upvote 0 Downvote
turkey3_scratch

turkey3_scratch

Expert
Ambassador
Jul 15, 2014
22,627
8
60,960


But that accounts for crappy units. A Corsair RM550x, Be Quiet Dark Power Pro 11 550W, EVGA 550 G2, etc. could probably handle handle two 1080s overclocked to 2100Mhz. Of course if he then overclocks the wazoo out of the CPU then it may end up posing an issue, but otherwise Guru3D's recommendations seem silly to me.
 
Upvote 0 Downvote
17seconds

17seconds

Champion
Jul 27, 2010
10,584
4
51,965

I'll stick with the experts who've been giving power supply recommendations for over 15 years, and who understand that providing a decent level of power overhead is essential to a healthy high-performance system. Way better than rolling the dice, cutting it close, and hoping that a clearly underpowered system will "probably handle two 1080s" while maxed out, fans blowing as hard as they can with heat rising up off the unit. The PSU is the beating heart of a PC and should never be sold short as you suggest.
 
Upvote 0 Downvote
turkey3_scratch

turkey3_scratch

Expert
Ambassador
Jul 15, 2014
22,627
8
60,960
The guys on Jonnyguru would have to disagree. I think if you overclock the 1080s then yes, a 650W PSU is more ideal. But we are talking about 180W GPUs here. Simple mathematics add those up to 360W. A typical CPU, 100W, and that makes your typical system with two GTX 1080s 500W (so that 516W is actually a solid approximation) about under full load.

Good units are designed to be able to run at that type of heavy load. And you'll find in units like the RM550x that the fans blowing as loud as possible is under 40db, making fan noise not even loud. Then you have 750W units that have louder fans running the same hardware. Or some units have better fan curves.

There really isn't any sort of "power overhead" because a power supply won't hit a limit on power (computer ones, that is). You can read about this Jonnyguru discussion I had here http://www.jonnyguru.com/forums/showthread.php?t=13311

According to the experts on there, a power supply won't ever hit a limit on power unless protection circuitry is overridden, a particular type of load is applied, and a specific internal design is employed that prevents the PSU from burning before the limit is reached. And with the really non-professional Guru3D PSU reviews anyway, I wouldn't listen to their recommendations as is.

I'll agree that 750W is the sweet spot for efficiency with two GTX 1080s. But nonetheless, will run perfectly fine on quality 550W units.
 
Upvote 0 Downvote
D

ddferrari

Distinguished
Apr 29, 2010
388
6
18,865


It's called sarcasm.
 
Upvote 1 Downvote
You must log in or register to reply here.

TRENDING THREADS

Latest posts

Moderators online

Share this page

COMPANY
RESOURCES
FOLLOW
Top Bottom