Hi. I recently picked up a 1080 Ti and have been enjoying it a lot, but noticed whenever I use DSR and play games in 4K or run a 4K bench like Fire Strike, my overclock pretty much disappears.
 
So a little information about my setup:
 
- 1080 Ti is liquid cooled with an EVGA AIO.
- It never goes above 50C.
- It doesn't matter if I have the Voltage and Power Limit maxed out or not.
- I'm running it at 2050MHz(+160) and +600 on the memory, BUT it does it at stock clocks too.
- I have a 1440p monitor 144Hz Gsync
 
Basically, if I run any resolution above 1440p, my core clock (when set to 2050) will go all the way down to 1850s even though my temps aren't even above 45c yet. As soon as I drop back down to 1440p, my clocks shoot up to 2038-2050MHz again.
 
I've taken a couple screen shots showing what I mean. These are from Fire Strike Ultra. If anyone can explain why it's doing this, I would appreciate it. Thanks.
 
EDIT: And notice how the voltage is really low? I have it set to go up to 1.075.
 
Card at completely default settings:
http://i.imgur.com/AmvMRMJ.jpg

Card overclocked:
http://i.imgur.com/Ff0hXFa.jpg

 
Here's regular Fire Strike (1080p?) with card overclocked:
http://i.imgur.com/g8txjge.jpg

 

I use DSR because it makes games so much smoother looking than AA and doesn't take the hit in FPS as much, either.

Thanks for the reply. I'll post some benchmark results as soon as I get home.

And as for the memory, I do remember that. I tested from +300 using +50 increments. It kept increasing my score until I got to +550.

ericc191
http://www.3dmark.com/3dm/19308886
 
Used your card's settings and the scores are pretty much identical for the GPU. But if it is a power limit issue, why does it stay boosted so high for 1080 as opposed to 1440/4K? Just less stressful on the card?
 
 

Yes. 4K is more stressful on the GPU. At 1080p the CPU becomes more of a limiting factor.