3-way SLI: Is it worth it?

TheDepressedTurtle

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Oct 31, 2013
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So, early next year I am thinking of building a new system and, if things go right money wise, I will be able to afford three GTX 780 DirectCU II's. How long would three of those cards be able to max games for at 1440p on a single monitor? And will they work on the Asus Formula VI motherboard? Thanks in advance!
 
Solution
Hey,

1) A PHYSX addon card can easily drag down performance. It varies by the game and PHYSX setting but if the main card is waiting for a slower card to process the PHYSX calculations the game just slows down. Just avoid this. Plus it adds a lot of heat. Linus from Tech Tips already did tests with this.

2x780's + 660? No. bad, bad idea.

2) 3xSLI:
Tom Peterson gave a demo and talked about how 2xSLI is working great but 3xSLI can actually cause issues. More heat, little performance difference and issues as well. Avoid.

3) 2560x1440 vs 1920x1080
I mostly game at 1920x1080. In a game like Skyrim the difference is barely noticeable; the text is only slightly fuzzy and you won't even notice after a while. There's about a 30% performance...

Spinny99

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May 28, 2013
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Lets just say you won't need to upgrade...for a really long time. The Asus Formula VI should definitely support 3-way SLI. Personally, if you're going to be playing on a single monitor, I'd only 2-way SLI 780's, and buy Hydro Copper versions and watercool them.
 

TheDepressedTurtle

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Oct 31, 2013
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My budget is stretched as thin as it can go with the 780s and as far as I know the Hydro Copper versions are considerably more expensive and I won't have any money left for a custom loop. Is the watercooling necessary or could I get by just using the cards fans?

 

aznricepuff

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Oct 17, 2013
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I have two reference GTX 780s in SLI and I have no problem maxing games at 1440p with AA turned off and getting at a minimum at least 60 FPS. With 4xMSAA the only game I can't manage 60+ FPS is Crysis 3 (I still average above 60, but sometimes the framerate drops to ~50). No watercooling here btw. Reference coolers do a fine job even with both cards overclocked to 1 GHz (1123 MHz boost).

Scaling on the third card in SLI is not amazing (it's still significant, but not as much as with the second card). I'd personally stick with two 780s unless you are thinking about going to triple surround or 4k resolution in the future.
 

Spinny99

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May 28, 2013
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Watercooling is not necessary, but will improve your overclocking performance, and make up significantly for minus 1 card. It'll also make it much more silent. They are a bit more expensive, $699 on amazon. So, think about it like this.

699 x 2 = 1400
vs.
550 x 3 = 1650

You'd have 250 left over, and would need to put around 250 more in for an epic watercooling system, and in my opinion it's worth it. It also looks cool too. Another option is 3-way SLI 770's (Asus in particular), which in some cases beats 2-way SLI 780's. Another option is your 2 780's, but add in a 660 to dedicate to PhysX.

It's really up to you bro.
 

TheDepressedTurtle

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Oct 31, 2013
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I heard that adding a dedicated PhysX card can actually drag down performance. Or is that only if I add something like a GTX 460 to dedicate to PhysX? Thanks anyway, I might invest in a liquid cooling system but I'll make the decision closer to the time when I'm building the system.
 
Hey,

1) A PHYSX addon card can easily drag down performance. It varies by the game and PHYSX setting but if the main card is waiting for a slower card to process the PHYSX calculations the game just slows down. Just avoid this. Plus it adds a lot of heat. Linus from Tech Tips already did tests with this.

2x780's + 660? No. bad, bad idea.

2) 3xSLI:
Tom Peterson gave a demo and talked about how 2xSLI is working great but 3xSLI can actually cause issues. More heat, little performance difference and issues as well. Avoid.

3) 2560x1440 vs 1920x1080
I mostly game at 1920x1080. In a game like Skyrim the difference is barely noticeable; the text is only slightly fuzzy and you won't even notice after a while. There's about a 30% performance hit to go to 2560x1440 which even at 60FPS adds to stutter.

So a single GTX780 would do you VERY nicely and just take the time to tweak a little if needed.

4) G-SYNC:
Read up on this. Basically requires a new monitor so if you're still looking I'd wait. It's truly awesome tech which solves all the issues with lag, tearing and stutter (well almost).

*In fact, my advice is get a single GTX780 then put your money towards a G-Sync 2560x1440 monitor when available if you don't have the high-res screen yet.

G-Sync is a game changer. If you don't think it's amazing you likely don't quite understand it. For example, you can get a similar experience at 50FPS as you would without using it but at 120FPS so you need less hardware to achieve a similar lag-free, stutter-free experience.
 
Solution

TheDepressedTurtle

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Oct 31, 2013
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Thanks, chose this as the solution. I will get 2 780s, or 880s, depending on when I build the system and I will invest any money I have left into a G-Sync monitor!
 

determinologyz

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Sep 21, 2012
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"3) 2560x1440 vs 1920x1080
I mostly game at 1920x1080. In a game like Skyrim the difference is barely noticeable; the text is only slightly fuzzy and you won't even notice after a while. There's about a 30% performance hit to go to 2560x1440 which even at 60FPS adds to stutter."

Ive tested a 1080p monitor after getting use to 1440p and its more then just text being fuzzy everything looks eh lets just say i wont go back to a 1080p unless i really really really have to