Gpu clock steadily decreasing under benchmark as i overclock over 100mhz on Evga gtx 780 sc

[ullert]

I have been trying to overclock my gtx 780 to squeeze every last drop of performance out of it, but as i push the Gpu clock offset over 100 mhz i start to see worse and worse performance in both games and benchmarks. I am not experiencing any artifacts so far. The temperatures are ok as well, with 50C at idle and 65C at full load (95% fan speed)

I am running evga`s precision X software on a second monitor, and by looking at that while the benchmark is running i see that the gpu clock goes to about 800-900 mhz?? which returns up to a steady 966 mhz when the test is over(while its in idle.)

I also have a gpu monitoring software (also evga) to look at power usage, which is in the range of 70-90% (with the precisionX Power Target set to 106%) So what exactly is holding it back or actually "downclocking" it when running a benchmark/game??

Update: So, i enabled Evga`s KBoost which locks the gpu at max speed. And it worked while at idle or light gaming, but as soon as i did some benchmarks (3D Mark and tomb raider 2013 bench) the card "throttled" to about 930mhz while at acceptable temps, Also the Voltage never exceeded 1150mV(standard) even though i have it set to 1200mV

 

[noidea_77]

Overheating?

 

[ullert]

Overheating?

Sorry for not answering earlier, i forgot to mention that temperatures are not a problem i am at about 65C at max load, (with fans at 95% speed) at idle the card is at 50C

 

[Michael Clancy]

Run the same tests again this time everything at stock settings. Report back temps and max core boost. Also what is/was your power limit setting? Ive seen similar things happen on my 960 without temp issue however if u look at the graphs in the precision x related to power/limit/voltage/max etc u will start seeing bouncing from 0 to 1 and back at least when my symptoms occured. You may be unlucky as i was... my core could only be boosted 13mhz stable..
i suggest after doing your stock baseline bumping in smaller 10-20 mhz increments
when you srart seeing the throttling pay attention to the graphs i mentioned above. Play with volt and smaller mhz increments.

 

[Michael Clancy]

Ideally you want your power limit volt limit etc as a straight line with a value of 0, when you go as far as you can it will be a solid 1 or oscillating between 1 and 0. Im 99% sure your graphs when u see this throttling they are oscillating or solid 1s.

 

[ullert]

Run the same tests again this time everything at stock settings. Report back temps and max core boost. Also what is/was your power limit setting? Ive seen similar things happen on my 960 without temp issue however if u look at the graphs in the precision x related to power/limit/voltage/max etc u will start seeing bouncing from 0 to 1 and back at least when my symptoms occured. You may be unlucky as i was... my core could only be boosted 13mhz stable..
i suggest after doing your stock baseline bumping in smaller 10-20 mhz increments
when you srart seeing the throttling pay attention to the graphs i mentioned above. Play with volt and smaller mhz increments.

Well i steadily kept getting better and better performance on benchmarks up to about 90mhz+ on the gpu clock offset and 190mhz on mem clock offset.

After i posted last time, i decided to play tomb raider to see if i still had the same issues in-game and for some reason, no. It seems like i only get the throttling while i do the benchmark. when i ran tomb raider, i played at 1241mhz(full speed) at 69-70C with voltages even reported going over the 1200mV setting i chose (though only by about 3-5 or something like that so probably just a false reading or something)


Also i didnt quite get what you meant about the 0 and 1 readings...

 

[Michael Clancy]

In precision x 16 if you double click the grapgs it will pop up a window and u can scroll up and down the graphs... if you look at voltage limit the graph will give u values of 1 and 0 only........ there are other graphs will the same i just dont know names as im at the neighbors right now... but that's what I'm taking about

 

[Michael Clancy]

Yeah my card 9nly likes 13 core but i can do 450 memory

 

[ullert]

In precision x 16 if you double click the grapgs it will pop up a window and u can scroll up and down the graphs... if you look at voltage limit the graph will give u values of 1 and 0 only........ there are other graphs will the same i just dont know names as im at the neighbors right now... but that's what I'm taking about

ok, so the hardware monitor was a function i was unnaware off

Now my Voltage limit does indeed display only a 1, so what does that indicate??

Update: Ok so i decided to start up tomb raider and run a benchmark with the monitoring running, and i tried to make it so you can see whats happening when the voltage limit goes from 1-0.

Green: when i fired up the game and looked at the start menu
Red: when the benchmark loaded
Blue: while the benchmark was running
yellow: when i stopped the benchmark

For some reason it jumpet back and fourth between 1 and 0 (under the green line) for a couple of seconds right after the game had launched, then it settled at 0 while i looked at the menu. You can also see the fps drop in the framerate graph below as the benchmark was running.


Here is a graph off the clock speeds during the benchmark aswell, it keeps lowering the clock to about 800mhz before returning to normal when idling (i have kboost turned on during these tests) Temps was as usual staying below 70C, with temp target set to 95C

And here is a graph showing stats while i played Tomb Raider