What is SLI?

[TheDirtyDiddler]

Hello all,

 

     I was wondering what people meant by "SLI". I've just started getting into computer technology, by that I mean gaming with a full on gaming pc. I am tempted to get a new GTX 970 to slightly increase performance, even though I have a GTX 960 already. I was browsing a life hacker article (http://lifehacker.com/5972503/what-should-i-do-with-all-my-old-outdated-computer-parts) and said I could reuse the GTX 960 as a dedicated graphics card for PhysX using SLI, and that's where my question comes into play. So, to recap, "What is SLI" and "Could I SLI a GTX 960 and a GTX 970?" (ps I have a i5-4690k w/ a ASUS z97-A)

[TheDirtyDiddler]

To be more specific, the GPU I have is here (http://www.amazon.com/EVGA-GeForce-128bit-Graphics-04G-P4-3966-KR/dp/B00UOYQ5LA) and the GPU I might get is this (http://www.amazon.com/Gigabyte-GeForce-Overclocked-GDDR5-GV-N970IXOC-4GD/dp/B00OQUMGM0)

[Pugs501]

nope, that's a 970

Now some AMD cards can do that but I'm not very knowable about AMD GPU's

[d3sl91]

So, to recap, "What is SLI" and "Could I SLI a GTX 960 and a GTX 970?" (ps I have a i5-4690k w/ a ASUS z97-A)

See video above. 

 

And no, cannot sli different cards

[Oshino Shinobu]

Essentially. SLI is two cards working together to render frames. You cannot SLI a 960 and a 970 together. It must be the same GPU, with the same amount of vRAM. Speeds, brand and size can all change, so long as they are the same GPU (so a 970 with another 970, or a 980Ti with another 980Ti) and the same amount of vRAM. 

 

Running a card as dedicated PhysX is possible, but it does not require SLI. It is also pointless with high end cards like the 970 and 960. You'd be better off selling the 960 than using it for PhysX. It will not improve performance, will generate more heat, consume more power and not all games use PhysX in the first place. 

[Sauron]

You CANNOT sli two different cards; unlike crossfire, sli requires the card to be exactly the same (or rather, to have the same name, meaning 970 or 960 etc). You CAN use one card as a dedicated physx processor - you don't need sli for that, but honestly the performance gains are absolutely minimal.

 

I really wouldn't upgrade to a 970 if I were you, the gap isn't big enough. What could sort of make sense would be to sell your 960 and get an r9 390.

[Oshino Shinobu]

See video above. 

 

And no, cannot sli different cards

That's a bit vague. An ASUS Strix 970 and an EVGA SC ACX 970 are different cards, but they can be put in SLI. It is the GPU and vRAM that matters. 

[TheDirtyDiddler]

Ok, thank you all

[Sauron]

nope, that's a 970

Now some AMD cards can do that but I'm not very knowable about AMD GPU's

 

with crossfire you can use any 2 (or 3 or 4) cards that use the same gpu die. For example, a 7950 can be crossfired with an r9 280x because the gpu core is the same even though it's cut down; the 280x will only use part of its gpu and lower its clock speed to emulate a 7950. The result however is nothing better than two 7950s in crossfire. Some cards (r9 x90/x cards, furys and I think tongas) don't require a bridge and crossfire in general does not require a specific pcie bandwidth - you can crossfire with pcie 1.0 1x slots if you wanted to (that doesn't make any sense, however pcie 3.0 4x works just fine for crossfire).

[SPAS-ID]

Chaining Same Nvidia Graphics Card to perform better

[Godlygamer23]

A correction needs to be made by the LifeHacker article. By running a dedicated PhysX card, you are NOT running SLI. The cards are completely separate and the game is simply calling on the PhysX card to do the PhysX processing. That's it. SLI with a 970 and 960 isn't even possible - they are not compatible with each other.

 

As an example, I run a 970 and 660 Ti together in my system. I have no options to put them in SLI, but can dedicate the 660 Ti to PhysX if I choose to do so.

[Leonard]

You guys didn't even noticed OP's formatting of his post, he has to be an English major, nicely done @TheDirtyDiddler, nicely done.