Reduce core to 1250-1300 and memory to 900(1800).
If the farm will not restart, then increase these values.
Try to test on a teamredminer.
When patching the upgraded BIOS, any problems may arise: The video output may stop working or the video card will turn into a brick.
Better to customize your graphics card yourself.
Thanks! The miner is still stable (after 31 hours) on my pic's config, you can check it in my post. If it crashes I will try your suggestion.
I already tested Teamredminer, it's not stable as well.get the name of ur bios
115-D182PI0-100 is the name for my asus 5600xt
then search for that with mod included
some dude compiled the majority of navi unlocked roms
i used the exact bios for my cards which helped
same with dude above mod everything urself just use the unlocked bios and copy everything over to it
i had problems with their TREF settings
my asus strixx samsung does still crash randomly with any bios mod ive tried
seems to run a lil better at 920-925 on memory than max
i get a lil longer in between reboots
u must be running phoenix? to get 43+ at 920
maybe try another miner
also u can run all the way down to 1100 on core at 700mV
might give u a bit more stability
setting VDDCI to 800 can help
but going lower u will run into problems
i used to get stability with MVDD at 1325 but with TRM config b it doesnt seem to do anything nor be enough to drop wattage
Thanks for the reply! 
My BIOS's name is: 115-D189P00-100, so the same. Where to search for mods?
I know that Phoenix miner inflates a bit the hashrate, but I'm okay with that.
Tried with VDDCI 750 and MVDD 1300, wasn't stable. Now it seems stable for the past 31 hours with the same clocks I posted in the original topic. You can check the link with pic.