Nvidia "SingleCard" vs SLI off + dedicated Physx Card ?

[jonathan1107]

Hi guys, trying to understand the nvidia panel a bit better. Quick question:

• If I select "single-GPU" from the "SLI rendering mode" option. What happens exactly? I notice it doesn't "restart" the driver so I'm guessing it still uses the other GPU for stuff like physx right? What happens exactly?
• What about when you "disable" SLI completly and dedicate the other card to physx.
• What about "force alternate rendering 1" and "force alternate rendering 2" ? What do these do?
  

 

[erocker]

1. It will use one card and the other card will be unused.

2. One card will be used for regular GPU stuff and the other card will be used for PhysX for PhysX games that used GPU accelerated physics... Which are few and far between.

3. Just different ways on how SLI renders. You normally don't need to bother with this unless you know the game doesn't work well with it being on auto and there's specific information on why a different mode needs to be used for that particular game.

 

[jonathan1107]

1. It will use one card and the other card will be unused.

2. One card will be used for regular GPU stuff and the other card will be used for PhysX for PhysX games that used GPU accelerated physics... Which are few and far between.

3. Just different ways on how SLI renders. You normally don't need to bother with this unless you know the game doesn't work well with it being on auto and there's specific information on why a different mode needs to be used for that particular game.

ya I'm specifically trying to get more performance out of my 2x gtx 980 ti's on borderlands 2 (which has physx)
They're barely getting GPU usage (around 30-50%) CPU same story, max usage is 50%

So I've been trying to find ways to squeeze out more FPS, thinking of trying the dedicated card to physx instead of SLI since I have almost no perf gain from SLI

 

[erocker]

Unless you have Vsync on or your frames locked you have an issue elsewhere.

 

[newtekie1]

Dedicating a card to physx won't help any. If you have that much GPU power left over, physx isn't waiting to be processed.

I'm guessing borderlands is very cpu dependent and not very well optimized for more than 2 threads(hence only seeing ~50% cpu use).

 

[jonathan1107]

Yeah I' spent A LOT of time trying to figure out how to improve the peformance (cause it was horrible) even with that much GPU horsepower.
I ended up realizing that Borderlands 2 uses dx9 and indeed isn't optimized properly (AT ALL)

It's in fact a lot like Skyrim. It uses a "grid system" for drawing/streaming textures and items. And that Grid is completly managed by the CPU and through means that CANNOT use today's CPU or GPU's ressources. Therefore the only solution for more Frame Rates is definitly to turn down that GRID Size. I lowered my view distance from ultra high to high and it made a WORLD of a difference.

It was quite astounding in fact. Indeed, poor optimization is a horrible plague in regards to PC gaming