OC Math, and is this OC worth it?

[Hotobu]

I have this card: EVGA 1080 TI SC Black 1670 Boost Clock 11000MHz Mem Clock

I am using the MSI Afterburner software for the overclock, and right now I have it set to +70 on the core and +175 on the memory yet (with Witcher 3 running in the background) in the program it says I'm peaking art around 1936 MHz on the core and 5670 on the memory. I have had to dial it back to these settings after several crashes even after using some stress testing. With that said I have some questions.

#1 How does the math here work. Even with a 1670 boost, +70 should be 1740. Why am I seeing speeds > 1900 MHZ on the core?

#2 I think I get the memory as (5670 * 2 -11000)/2 puts me almost right at the Memory overclock I'm using. Is this correct?

#3 Are such small OC measurements worth it? It's really hard to tell what kind of overall performance improvements I'm getting since the game runs very similar with or without overclocking, and I don't know if I should even bother with OC. This is my first time with this so I also don't know if 70 on the core and 175 Memory is good.

Thanks in advance for any insight.

 

[Jetster]

What resolution ?

 

[Hotobu]

3840 x 2160

 

[Toothless]

Crank the power limit as far as it can go, probably 117% which will put you a bit above 1900mhz. You can also stick a 200mhz bump on the memory and all should be good. You're currently not anywhere close to what a Ti can clock to.

 

[Hotobu]

I have the power limit to 120%.

 

[newtekie1]

How does the math here work. Even with a 1670 boost, +70 should be 1740. Why am I seeing speeds > 1900 MHZ on the core?

The algorithm that nVidia uses will almost always make the card boost way higher than the advertised boost clock. I bet even at stock you probably will see boost speeds near 1800-1900MHz.

 

[therealmeep]

At least with pascal, core offsets are done pretty much all by the card, it will boost up to where it can sit between 5 degree temperature offsets, usually around 1900-2000Mhz If you want the easiest returns, add 100 mhz to core, and focus on memory. I usually get about probably 400+ mhz on memory, but for the most part the card drives itself. I usually leave my 1080ti at “stock” which is probably close to 2ghz w/XOC bios (voltage unlock to 1.5v, no power limit) I run my card at 1.093v with 1999-2025Mhz core depending on the temp (40-50C on water) and stock memory.
With pascal temperature is key!

 

[Hotobu]

Ok, I think I may have figured out the problem. I never bumped up the core voltage. Right now I have the core voltage % maxed and am running +100 core and +400 memory and my temps seem to be hovering @ ~ 70C with 70% fan speed.

 

[Toothless]

Have you tried all stock except for maxed power limit?

 

[therealmeep]

Have you tried all stock except for maxed power limit?

I personally saw no benefit from this, just me

 

[Toothless]

I personally saw no benefit from this, just me

I've gotten from the 1552mhz or whatever my card is to 1972mhz on power limit alone. Saw a big difference in fps. Stock power limit I didn't get close to that 1900+ speed.

 

[Vayra86]

Adding 'additional core voltage' in my experience does not really add much except higher temperatures which is detrimental to the boost clock the card will hold on to.

Crank up the power limit slider to 120-121% (max it will do) and see how much you can get out of that.

Memory should go to +400~+500, going higher is problematic OR does not result in better performance. The memory controller gets weird above 5500mhz, stutter / instability / worse FPS are likely.

After that, see how far that core goes for your 1080. YMMV but most 1080's go from 1950 ~ 2100, beyond 2000 its very much silicon lottery and the voltage required increases rapidly.

My 1080 sits happily at 2000 / 5500 like this, with +130 on the core, temps stabilize around 75-83 C depending on ambient temperature.

The net gain on most 1080's from any factory OC to your own will be something around 5-7%.

About fan speed: generally the pre-defined fan curve on most cards is pretty solid, adding fan speed at any given temperature won't do all that much, what really matters is case airflow and ambient temperature. 70% I reckon should be quite audible, if its too loud you can also adjust the curve down a bit, and chances are it will barely affect temperatures.

 

[Hotobu]

So I don't know if it's the Witcher 3 that's problematic, or I lost the Silicon Lottery, but when my game freezes I have to dial it back. Right now I think I've settled on +80 clock and +370 memory. My temps have never gone above 75C

 

[therealmeep]

I personally have had shit luck with pascal oc'ing in game, hence why I leave it at stock, however if you want an oc stability tester, run arma 3 for about an hour.

 

[Vayra86]

So I don't know if it's the Witcher 3 that's problematic, or I lost the Silicon Lottery, but when my game freezes I have to dial it back. Right now I think I've settled on +80 clock and +370 memory. My temps have never gone above 75C

Somehow I gathered from your earlier OP that you had a 1080. Not a 1080ti. There are differences here; the memory most notably is already clocked higher out of the box so not getting +500 is reasonable. Also, big GPUs don't clock as high. The lower the TDP, the further Pascal can boost. 1070's for example get 2100+ mhz most of the time.

So don't sweat it about the silicon lottery, with these GPUs the differences between best and worst are really, really small.