Question GTX 780 ti inconsisent clock speeds in fortnite

[fagetti]

Im suddenly getting a issue playing fortnite where my clock speed either decreses or bumbs around 1000-1225mhz ingame. I used to get consistent 1225mhz on the core for my 780ti which didnt drop ingame. Now i get either 1150, 1080mhz and something in between which lowers my fps. Im not thermal throttling and issue is not the overclock itself, ive tried to decrease my core and vram getting similar issues, and this oc has worked for me for 2 years without a problem before. Tried to install latest drivers with driver display uninstaller without a luck.
I tried superposition and im getting similar scores than years before with my 1225mhz overclock, and my core clock STAYS at 1225mhz the full benchmark without dropping down. what could i try to max clocks in fortnite?

 

[renz496]

what is you exact load temp? to maintain the highest boost i think you need to keep the temperature below 74c.

 

[fagetti]

Load temp in fortnite is about 65-72c and i have set fans to 100% after 64c. However i dont get this problem in superposition everything maxed out 100% gpu usage i get 79c and still will be able to maintain 1225mhz clock for the full period of benchmark. There might be little 10mhz drops after 75-77c in benchmark but nothing major like in fortnite i lose 100-200mhz with 65c. Changing graphic settings in fortnite wont help either i get core clock drop with epic and low settings

 

[fagetti]

I recently bought new ram kit which is rated 2133mhz and i i tried to run it 1600 mhz to see the difference since im running gen1 cpu which is based on blck overclocking. Lowering blck didnt resolve the issue, also tried to reset settings in nvidia control panel and disable frame rate limit. No idea what is causing this, maybe its issue with fortnite only? whatever i do im getting a drop from 1225 to 1050mhz when entering populated area. and it fluctuates between that and 1225mhz

 

[fagetti]

any ideas?

 

[fagetti]

Issue is only happening when CPU is pushed hard, i can run whatever benchmark with my overclock and temperature stays fine and im getting good results. Also clock speed wont drop even by 1mhz on either core or memory its fully stable. However when i stress both CPU and GPU at the same time, gpu load starts to fluctuate between 30-80% instead of 100% what i get stressing only GPU benchmark. I tried to change my gpu slot from pcie 2.0 x16 to 2nd slot which is pcie 1.1 x4, strangely im getting 100% stable usage even when stressing CPU same time.
However my performance is affected by atleast 10% cause of the port being only 1.1 x4. Then i changed port again back to 2.0 and went default clocks on my cpu and ram speed down to 1333mhz and also degreasing my cpu voltage from 1.4 to 1.1v. IM STILL getting fluctuating gpu load when stressing gpu and cpu at the same time! even after disconnecting all peripherals and fans etc. My psu is almost new seasonic focus + platinum 750w.

It all points to the port being bad, but how it can give good good results with 100% gpu load when i stress only gpu with unigine example? issue is very weird

 

[fagetti]

i bought used 980ti to test same issue AND it is happening with this gpu also, i only tested pcie 2.0 port and im having similar issues whenever im stress testing cpu / gaming etc. Gpu load drops and fluctuates, So when GPU is not the issue what could it be? Would there be some option wrong in my bios example ? My mainboard is p7p55d and i tried stock clocks stock ram speed doesnt change the issue, Also limiting CPU speed to 2000 mhz from 4200 mhz and undervolting produces similar effect so this isnt psu related, my psu is anyway top of the line seasonic platinum 750w