Just built a new system from scratch. I'm using a gigabyte z170x Gaming 3 motherboard. I noticed that when Windows 10 (fresh install, not upgrade as this was a brand new build) starts the fans are either idling very slowly or in some cases not moving which makes sense if I'm not doing anything. However if I start Precision X (also tried MSI afterburner with identical results) the fans immediately spin up to full speed and will not cycle down again even if I'm not doing anything, just sitting at the desktop. I also noted that neither Precision X, Afterburner or even GPU-Z would not report GPU fan RPM, instead showing zero as the fan speed.
After speaking with an EVGA Tech I went through the process of uninstalling Precision X/Afterburner (we tried both apps) then uninstalling NVIDIA drivers. I then rebooted into safe mode and use the tool to remove any instances of Nvidia software or drivers. Rebooted back into windows and reinstalled NVIDIA drivers only (not the GE Force experience stuff). When I'm not doing anything the fans idle slowly however when I start a game (or launch Precision X) the fans once again power up to full speed and just stay there. After quitting the game and sitting on desktop the fans continue to spin at full speed and the only way to resolve is to restart windows. Last night I did see that Precision X actually recognized the fan RPM which made me wonder if the problem is intermittent. However after half an hour of hope Precision X once again stopped reporting fan speeds and the fans again spun up to full speed as has had happened previously. Check that the fan headers are secured on the graphics card so I'm left thinking that there's something wrong with the hardware and the GPU. Even tried using a different PCI-e slot with same results - just wanted to rule out the motherboard.
I'm now waiting for a replacement GPU card which I'll have to wait until Wednesday or Thursday since it's a public holiday tomorrow and Amazon cannot ship my replacement until Tuesday.
Just in case this is an issue that may have a solution that myself and EVGA Tech has missed I appreciate any responses, however I'm fairly confident it's a GPU hardware issue. On the bright side I can still play games until my replacement arrives, as the GPU is staying nice and cool with fans running at full speed! There's no system hangs, blue screens or reboots, so most likely a faulty fan controller board on the card.
Thanks for all and any suggestions in case I may have missed something.

it's not black screen & 100% fan speed ? , like this .. http://forums.evga.com/GT...p-to-100-m2530081.aspx

No black screens, no game issues. If I didn't have on headphones I would be none the wiser. Everything going along just great, except the GPU fans are going at what I'm sure is 100% and not reporting any info to the apps. I think the fact that they seemed to with last night for about 30 minutes before ceasing to report fan speeds and going back to full speed most likely points to a hardware issue with the card.
Like I said, Amazon sending me a new one so I'll just run this until mine arrives. On idle the GPU is 23 degrees! So the fans are doing their job!

have you installing msi afterburner to check what the fan speed is and trying to set fan speed manually.

Did the RMA fix your issue? I'm having the exact same issues with multiple cards.
 
Precision X says Fan Speed % and Fan Tachnometer, RPM are both 0. At the same time, the fans are actually spinning at full speed.