I believe this to be a software problem but I can find a fix other than rebooting my computer...
 

 
My GPU Clock gets locked at random speed ceilings.  I've seen numbers like 676, 1037, 1449, and 1708 where the clock speed will not break the ceiling.  It'll drop down to 253 when idle but not go above these seemingly random numbers until I reboot my computer.  You can see from the screenshot that it's not a temperature issue - the fan hasn't even kicked on here and the speed is capped.
 
Any insight to what's going on would be greatly appreciated.

you really need to provide a lot more info.
 
what drivers?
what card did you have before this?
did you do a clean install including removing any monitoring software like afterburner? 
what are your other specs including power supply?
are the issues happening in all games or is that some type of benchmark you were running?
 
 
 

This is with 368.39.  I had a GTX 770 where I uninstalled old nvidia drivers and started with 368.39, checking the option for a clean install.  No other GPU software was installed.  The cap is present with every game once it starts.  I'm using the below:
 
4790K
ASUS Z97
16GB 1866
EVGA 750W PSU

I've restarted in Safe Mode and run DDU to remove drivers.  The same problem has occurred while launching The Division, seen below:
 

No driver crashes at all.  I'd never installed OC software before this problem.  I installed the newest EVGA Precision after the problem with the hopes that it'd help.  I've since removed it.
 
I've rebooted and below is a current GPU-Z capture:
 

peterscott00
I believe this to be a software problem but I can find a fix other than rebooting my computer...
 

 
My GPU Clock gets locked at random speed ceilings.  I've seen numbers like 676, 1037, 1449, and 1708 where the clock speed will not break the ceiling.  It'll drop down to 253 when idle but not go above these seemingly random numbers until I reboot my computer.  You can see from the screenshot that it's not a temperature issue - the fan hasn't even kicked on here and the speed is capped.
 
Any insight to what's going on would be greatly appreciated.

Change power management mode inside the nvidia control panel to prefer maximum performance, reboot pc, retest the division, results?
 

denny6371
default mem ck=1251mhz ??

That is correct. 1251x4 = 5004 x 2 = 10008

peterscott00
Thank you for the suggestion.  I'll try this tonight.  Would it be correct that a reboot might not be required?  In that setting max performance when the clock has been capped might uncap it immediately?  A reboot always clears the cap for a random duration...

If you set max performance inside the game profile itself you don't need to reboot. If you set max performance globally you will need to reboot.

peterscott00
Could leaving my PC on 24/7 be part of this?

I doubt it.

So I believe this problem is somehow linked to GPU-Z (It was always running through the days I experienced clock caps). 
 
I had set the Global Power option 5 days ago and haven't experienced the issue (based on watching familiar frame rates in games). 
 
Not running GPU-Z the entire time, I just launched it and now I'm running into the opposite problem.  After gaming for a couple of hours with GPU-Z running, my GPU Core Clock is locked at 1708Mhz after closing all 3D apps - It won't drop.  It'll go up to boost levels if I launch a game...
 
Maybe the Global Power option reversed the effect?

peterscott00
So I believe this problem is somehow linked to GPU-Z (It was always running through the days I experienced clock caps). 
 
I had set the Global Power option 5 days ago and haven't experienced the issue (based on watching familiar frame rates in games). 
 
Not running GPU-Z the entire time, I just launched it and now I'm running into the opposite problem.  After gaming for a couple of hours with GPU-Z running, my GPU Core Clock is locked at 1708Mhz after closing all 3D apps - It won't drop.  It'll go up to boost levels if I launch a game...
 
Maybe the Global Power option reversed the effect?

I doubt its related to GPU Z. My MSI Gaming X 1080 has very similiar issues. If my PC has been on for a while - a day or 2 - it would randomly cap the boost clock at something low like 1400- 1500mhz. A reboot always fixes it.
 
I have seen a few people online having this issue - I am assuming its driver related. 

Thank you for the input.  What exactly are you doing in device manager for the reset?
 
A few posts down confirms that the EVGA SC 1080 is a FE board with an ACX cooler.  I expect this to be 100% driver as re-installing the driver without a reboot fixes the problem.  This is incredibly frustrating.
 
I suppose it could be a GPU bios problem as well?

Sajin

peterscott00
So I believe this problem is somehow linked to GPU-Z (It was always running through the days I experienced clock caps). 
 
I had set the Global Power option 5 days ago and haven't experienced the issue (based on watching familiar frame rates in games). 
 
Not running GPU-Z the entire time, I just launched it and now I'm running into the opposite problem.  After gaming for a couple of hours with GPU-Z running, my GPU Core Clock is locked at 1708Mhz after closing all 3D apps - It won't drop.  It'll go up to boost levels if I launch a game...
 
Maybe the Global Power option reversed the effect?

Yep, setting power management mode to max performance under the global tab inside the nvidia control panel will keep the cards clocked up at idle. Set the power to max under the program settings tab (each game) instead. Leave it set to adaptive under the global tab.

+1
 
What version of Windows are you running?

Driver 368.69 was released today. Give them a try.
 

368.69 in debug mode and the clocks speeds are still capping.
 
I have to assume this isn't a wide spread problem, but is instead isolated to an environment versus nvidia driver issue.
 
What's the better avenue between an Nvidia bug report and EVGA tech support?

Reading through this thread again..     has your card EVER reached proper boost clocks which are usually around 1900 to 1930Mhz???    In all those GPU-Z screenshots it was showing power limited and running a very low voltage.   I'm wondering if something is up with your power supply.
 
I did have an issue a few years ago with a GTX780Ti which ended up to be a failed power supply.   Well it didn't completely fail as my PC would still boot up, but sometimes it would just randomly shut off.  I had to get a multi-meter to diagnose it but the power supply was only feeding about 2.5 volts from the 12 volt pcie 6pin connectors.   Basically the card wasn't getting enough power so would only show about 28-30% power usage, which is similar to the problem your seeing under the TDP%.
 
I don't know if you have a multi-meter around to test or maybe it's something as simple are a loose connection on those PCIE power cables.