are you sure it is the gpu usage and not the power usage ?
If it is gpu usage it shouldn't unless, may-be, if you use a very old version post killer groeslt (and even then I never see anything like that). However the power usage varies quite a lot...
also the mem clock seems low (I am 2740MHz or do I have to divide by two ~1370 ?).
I get ~2700MH/s on X11 (more or less original one) with a core clock of 1350MHz...
no after that all card behave a bit differently from each other...
My only advice, try to use a recent version, there is parameter to adjust...
I got it to 2400kH/s and I am looking at the GPU usage thru GPUz, actually when I am not logged in (when windows turns the monitor off) it stabilizes.
I am looking at the frequencies from GPUz as well, so IDK.... is my mem too low???
I guess I should experiment with freq. but am I using the right miner:
ccminer35-50.exe and
337.88 WHQLI got it from IDK where.... wich one is the most optimized miner/kernel for X11
Thanks
check out cudamining.cc good site