PSU for SLI configuration

[maayan.lab]

Hello everyone.

I'm building a new PC and want to pick up a PSU.

 

Thing is, I'm going for GTX 980 Ti and later down the road I'll upgrade to 2-way and 3-way SLI.

 

So two questions.

First, the recommended wattage is around 600W for one GPU. How does it go with SLI? Obviously it's not 1,800W for 3-way SLI.

And second, if I'm going for the big wattage (capable of dealing with 3-way SLI), then put only one GPU in the system, and most of the power is unused... Any harm in that? What are the consequenses?

 

Thanks everyone.

[RoroTheDeer]

First, a video from Luke that answers the question about PSUs drawing more power than they need to:

 

 

 

Secondly, if you're going to be using 3-way SLI in the future with 980Ti's, I would, personally, buy a 1000/1200W PSU now that has a high efficiency rating (say, maybe a 1000W P2 from EVGA? It does depend on what other components you'll have in your system). Your personal choice on the matter may vary, though.

[HKZeroFive]

Nope, a PC will only take as much power as it needs. Power efficiency depends on its 80+ rating.

 

To tell you the truth, a third GPU will have essentially very little performance improvement over two. The ideal amount of GPUs would be two.

 

850W for two way SLI

1000W for three way SLI

[TidaLWaveZ]

The recommended minimum for a whole system containing a single 980ti is 600w. The power draw for the 980ti is only 250w.

 

Whole system with 2 way 980ti = 850w and up

Whole system with 3 way 980ti = ~1100w and up(Don't bother with 3 Way SLi)

[STRMfrmXMN]

2 hours ago, maayan.lab said:

Hello everyone.

I'm building a new PC and want to pick up a PSU.

 

Thing is, I'm going for GTX 980 Ti and later down the road I'll upgrade to 2-way and 3-way SLI.

 

So two questions.

First, the recommended wattage is around 600W for one GPU. How does it go with SLI? Obviously it's not 1,800W for 3-way SLI.

And second, if I'm going for the big wattage (capable of dealing with 3-way SLI), then put only one GPU in the system, and most of the power is unused... Any harm in that? What are the consequenses?

 

Thanks everyone.

As everyone else said, don't bother with more than two GPUs as scaling will add like 10% performance for about 40% more money on top of your system. For two of them get an 850W EVGA GS/GQ/G2 and you're set.