Does having two different cards affect performance?

[WhatComesAround]

I honestly don't get what's going on. So from what I understood from topics I made years ago having two cards, say a 980 and 1050ti, not in sli, and one card not driving a display would be useless because the other card wouldn't do anything. But today the weirdest thing happened. I mine Zcash and while I was doing that I was also editing a video but I noticed that both cards were doing horribly while editing in terms of mining performance. So does this mean that both cards are working to render what I'm seeing? What does the second card do and why is it involved at all with what I do? I thought it would just be doing it's thing there while my 980 is working on whatever it is im rendering or whatever. Can someone explain what's going on? And does this mean there is an advantage to having two cards even if they arent in sli?

[Egg-Roll]

If the software is CUDA enabled it likely uses both cards and not just the one your screen is hooked up to.

I know you can use the second card as a screen extender (adding more monitors), but afaik if the program allows CUDA or the function nvidia has for computing power combination, yes it will use both.

[Crunchy Dragon]

The second card can also be used as a PhysX processor for games that require PhysX(Goat Simulator for example).

[WhatComesAround]

13 hours ago, Crunchy Dragon said:

The second card can also be used as a PhysX processor for games that require PhysX(Goat Simulator for example).

 

13 hours ago, Egg-Roll said:

If the software is CUDA enabled it likely uses both cards and not just the one your screen is hooked up to.

I know you can use the second card as a screen extender (adding more monitors), but afaik if the program allows CUDA or the function nvidia has for computing power combination, yes it will use both.

Very interesting info, thanks a lot. Will look into PhysX and CUDA more. This a great added bonus because I thought that the 1050ti would be used for anything apart for mining, I will also be getting another two 1050ti's because my first one was just used to get proof of concept. With everything tested and ready I can go ahead and get two more.

[Serin]

Pull up two instances of GPU-Z, one for each card. See whats going on.

And yes, many programs can access two different cards to render stuff. Blender for instance just has check boxes for each GPU in a system.
Plugging ones monitors into the non-rendering card(ie the less powerful one) is a good way to avoid system lockups.
SLI isn't relevant to any of this.