GTX 970 mini - undervolting fixed black screen and allowed to overclock, but why?
Hello all, I'd like to share my weird experience with tweaking my graphic card.
My card model is GV-N970IXOC-4GD - Gigabyte GTX 970 mini OC. When I bought it like 2 years ago, I didn't like how much noise it's generated under load, so I switched the stock cooling to Arctic Accelero Mono Plus. The temps went down from 80C to 60C under full load and it was reaaaally quiet. I was happy with that result, but pretty soon some problems started to show up.
After couple of weeks when playing some games, I started getting black screen with sound issues (pretty know issue). The list of games which had this issue was pretty random, here are some examples:
Games which worked OK - League of Legends, Witcher 3, all Mass Effects, Starcraft 2, Path of Exile.
Games with black screen issue: Grim Dawn, Battlefield 1, Tomb Rider games, Far Cry 4 and Primal.
I didn't see much connection between the games, Grim Dawn is not GPU intensive and it crashed. Witcher 3 is GPU intensive and it didn't crash.
I fixed that witch just underclocking the core frequency to be max 1200 mhz under full load. The card was quiet, so I was happy with that result. Lately I have started to tinker a bit, to maybe somehow overclock it. Giving the card more power or overclocking it even by 10mhz resulted in black screen again. I could only overclock the memory by +300mhz with no issues. So I started tinkering with Bios.
I tried different settings, tested in some benchmarks, nothing seemed to work, until I finally had a brakethrough - completely changing the bios to have:
- the max core clock boost at 1329 mhz
- max voltage at 1.162V
- memory clock at 3800 mhz
- max power target at 97%
Boost:1241 MHz/ Base: 1101 MHz in OC Mode
Boost:1216 MHz/ Base: 1076 MHz in Gaming Mode
It also resulted with lowering the temperature to 53C max under full load when playing games like Kingdom Come or Witcher 3 for couple of hours. So I both overclocked and lowered the power consumption. 0 black screen.
So now... What the actual F? Why does this work and with any higher voltage I was getting the black screen? Maybe my GPU VRM's were getting too hot with higher voltage - but was that even possible with only 60C on GPU core? Well, I do have additional heatsinks all over the card, I even installed a small 40mm fan right above the VRM's. It didn't change anything.
How is that even possible to both overclock and undervolt?
Last edited by Pivuu; 03-16-2018 at 02:19 AM.