WatchDogs2: 2nd GPU slot = Worse performance?

[HungryHamster]

Hey everyone,

 

I'm not sure if anyone can give me an answer, but I'm wondering why my GPU in the 2nd GPU slot performs worse than the one in the primary GPU slot. I'll explain my issue/concern...

 

I got Watch Dogs 2 and I have 2x GTX 1080's SLI'd with the HB bridge and an i7-6700k. I've been getting crashes running SLI (even with latest drivers) so I wanted to try it with 1 GPU.

 

So I disabled SLI in Nvidia control panel and the game does not crash, but it's automatically utilizing my top card which obviously gets hotter than my bottom card. I didn't think there was a way to change this, but then I found that Watch Dogs 2 lets you select which GPU you want to utilize. So I switched it to the 2nd GPU and restarted. I immediately noticed that despite being identical to the top card, it was getting about 20-30 less FPS.

 

Why? Maybe because it is dedicated to physx as well or maybe because the default is to utilize the card in the top slot when using 1 gfx card? Do I have an issue with this card or is it normal for performance to be much worse in the 2nd slot?

 

Any help would be appreciated.

 

Thanks

 

[samcool55]

Is your monitor connected to the top card or the bottom card?

If it's connected to the top one, and you are trying to game on the bottom one, there's an extra delay because the image needs to go from the bottom card to the top card and it's possible that's causing the issue.

[HungryHamster]

27 minutes ago, samcool55 said:

Is your monitor connected to the top card or the bottom card?

If it's connected to the top one, and you are trying to game on the bottom one, there's an extra delay because the image needs to go from the bottom card to the top card and it's possible that's causing the issue.

Now that you mention it...

 

Yeah, it is plugged into the top card and I was trying to run the game solely on the bottom card. You're probably on to something. I'll test it out switching the connection

[SCHISCHKA]

theres also less lanes on the bottom slot depending on motherboard. Iv been trying to find if there is a performance difference with the latest GPU on these slots

[HungryHamster]

21 minutes ago, samcool55 said:

Is your monitor connected to the top card or the bottom card?

If it's connected to the top one, and you are trying to game on the bottom one, there's an extra delay because the image needs to go from the bottom card to the top card and it's possible that's causing the issue.

I think you were probably right. At first it didn't make a difference, but then I enabled SLI in NVCP and set the game to run on only 1 GPU. Seems like I have the same frames as my top card was getting so I'm definitely less worried. Thanks for the help!