SLI, UE4 and physics

[anonymous_user_c13016e3]

Sli

@Kensei;221443

Instead of getting the Titan with the outdated architecture, I opted for a 980, but seeing how the titan has a 12 gigs vram and the 980 has only 4gigs, i got another 980 and hooked them up for a theoretical total of 8.

Question now is:
**1.**Does UE4 utilize both buffers or is it only filling the main one?
**2.**Does dedicating a GPU for PhysX do anything in UE4, or are physics solutions locked to CPU for compatibility reasons?
**3.**Does the second GPU (assuming its dedicated to PhysX) help with rendering when it’s not used at 100%?
**4.**Does it matter where I connect a second monitor? If it does, does this mean that if I connect it to the second 980 that I’d be eliminating SLI, or will both cards help each other with rendering? I’ve done some research and I’m aware of the fact that there’s a main SLI rendering screen that is defined in the control panel, but that’s pretty much all it says.
**5.**And lastly, the main reason I got 2x980’s is because I’m really excited about the FLEX unified solution, and I was really hoping to utilize the new Maxwell architecture with UE4 and dedicate a GPU for the flex solutions, so does anyone know if PhysX will remain locked to CPU?

I’ve gotten SLI to work with a nice performance boost over single gpu with nvidia inspector and using the farcry primal profile and then directing that to the \Program Files\Epic Games\UnrealTournament\UE4-Win64-Shipping.exe then in the nvidia control panel set sli rendering mode to force alternate frame rendering 2 otherwise you get flashing artifacts and alternate frame rendering 1 crashes the game alot. I also use adaptive vsync

cheers