Hi guys,
 
Last week I upgraded to the EVGA 1080 SC ACX 3.0 and got it last Monday. It had issues with fan fluctuation while under load. The fans would rev up to 3800+ RPM's randomly and go back down under load. This did not happen when there was no load. It followed the EVGA Precision XOC profile I gave it when there wasn't a load. 
 
I called up EVGA and told them about the issues, so I purchased the Advanced RMA to get a new one and they got me sorted out. Got my new GTX 1080 SC ACX 3.0 today and now I appear to be having the same issues, which makes me wonder if it's somehow me. The fans don't rev at all when there is no GPU load (i.e. when not playing games) and they always follow the Precision XOC fan curve I made for it. However, as soon as I started Mafia 3 (and other games, it's not just limited to Mafia 3), the fan revving started again with my new card. It would shoot up then back down and it seemed all over the place. As soon as I quit the game, the fans go back to normal. I really don't know what to do about this, and it's really annoying hearing the fans rev when gaming. This never happened with my old GTX 980 Ti.
 
I uninstalled my old drivers before installing the new ones, and I did a clean install on the installer. I tried reseating the card, replugging in the VGA power connectors, nothing. I even uninstalled and reinstalled Precision XOC with admin rights, and I'm running it as an admin as well. 
 
My specs are:
 
Windows 10 64 Bit
MSI Gaming 5 Motherboard
i7 4790K @ 4.0 GHZ with Corsair H100i v2 watercooling
16 GB DDR3 RAM
Nvidia GTX 1080 SC ACX 3.0
EVGA SuperNOVA 850 B2 80+ BRONZE 850W Semi Modular PSU
 
I've also uploaded two photos of what Precision XOC shows me while gaming. One other thing I noticed is the GPU Clock went up as high as 1999 MHZ, so I'm not sure if that's normal or not for the 1080 SC.
 

 

 
 
 

Phoenix864
Everything is normal. The fan revering is a somewhat uncommon issue with the ACX cards. However, if your fan does not rev when using a custom fan profile you are fine.

It revs under load when using the custom fan profile. It will not rev at all when I'm not gaming while using the profile.

I'm just starting to wonder if it's some setting somewhere. This is my second brand new 1080 SC in less than two weeks. This happened for both of them, and they both came direct from EVGA.

If you are determined to keep your card, purchase a hybrid kit, install it and see if your issues persist.

 Try uninstalling EVGA Precision XOC and see what happens then you could try MSI Afterburner to see if that fan profile works better. Just a thought :/

Hopefully he don't have enough both runing at the same time!

So what about if you don't use evga's precision x?? Did you close that and try msi afterburner?

So I was having this issue and the first RMA I did didn't fix the issue. In fact, the second card was even worse. They sent me a second RMA and it works PERFECTLY. It even runs way cooler which may be a symptom of the fans not revving to super high RPMs randomly for no reason. So it IS possible to get a working one through RMA.

EDIT: I'd like to point out that with my original card, I tried: 4 different drivers, reseating the fan power cable, reseating the entire card, 2 different power supplies, 2 cases, different power cables, MSI afterburner, Precision OCX, 3 different BIOSes, and updating the BIOS to my motherboard. NOTHING fixed it. The fans were perfect unless the card was under load and then the fan would start going crazy.