Can anyone tell me how this switch works and what BIOS is activated on the OC switch? Exactly what changes take place? Also, how can I see what bios versions are on the card in the normal and OC roms? How do I flash a bios to one of the positions? 

It changes the fan profile and eliminate the 0 fan speed

Anyone know if flashing to Asus strix oc bios will void the warranty? How can evga even tell if later on I flash to stock bios.

fofal
Anyone know if flashing to Asus strix oc bios will void the warranty? How can evga even tell if later on I flash to stock bios.

Depends. My understanding is that is the whole point of having two BIOS options on the card. If your modified BIOS doesn't work, you still can go back to your other BIOS to fix the bricked one. You should always backup your existing BIOS prior to modifying it in any way. Now if the mod results in any damage to the card and you're unable to flash the old BIOS back, they may potentially deny the warranty claim.

I wonder if the OC bios switch is whats causing this buzzing issue:

Hi all, just got my RTX 3090 FTW3 Ultra yesterday and i am having an issue trying to enable the OC bios switch on the gpu itself. I turned my pc off, flipped the switch from normal to OC turned my pc back on but nothing changes, the fans still dont spin up. I thought they were meant to be permanently running when you flip the switch and then the speed fluctuates depending on the temps?
 
I m on the standard bios version that was on the gpu when i got it.
 
Any help would be greatly appreciated.
 
Thanks
 
F1A 

Hi, thanks for the reply, I did try that, saw it in another post but it did not work. I saw there was a new update to precision X so installed that and at the end of the instal process it said something about some changes and to restart for them to take effect, I did so and then the fans seem to seem work in OC mode as they are meant to.
Haven't been game enough to run precision X again yet in case it does something to the fans. On prior version all all could get to work was manual fan control, could not get the custom fan curves to work, the fans would just not come on. Assuming there was a glitch somewhere.
Might try the fan curves again at some stage. Does OC mode override precision X fans or vice versa if you set them?
Not sure how that part of it works. This is my first EVGA card
Cheers

F1Aussie
Hi, thanks for the reply, I did try that, saw it in another post but it did not work. I saw there was a new update to precision X so installed that and at the end of the instal process it said something about some changes and to restart for them to take effect, I did so and then the fans seem to seem work in OC mode as they are meant to.
Haven't been game enough to run precision X again yet in case it does something to the fans. On prior version all all could get to work was manual fan control, could not get the custom fan curves to work, the fans would just not come on. Assuming there was a glitch somewhere.
Might try the fan curves again at some stage. Does OC mode override precision X fans or vice versa if you set them?
Not sure how that part of it works. This is my first EVGA card
Cheers

Maybe you are having the same issue that is described here: https://forums.evga.com/FindPost/3156677

Hello. I updated my EVGA 3080 FTW3 Ultra Gaming card's bios to the OC one. Now, I see in Precision X1 that the power limit can be increased up to 118%.
If I leave all the settings to stock settings (i.e. 100% power limit, 85° GPU Temp, Clocks to "0"), am I right to assume the BIOS doesn't change anything except for the fans to run above 1000 RPM all the time ?
In other words, if I do not do any change in an overclocking software such as precision X1 or Afterburner, doing this OC Bios won't increase power draw, voltage or anything else (just the fans RPM).

If so, is it ok to uninstall Precision X1? And maybe use Afterburner (just for the OSD and FPS frame limiter ; no OC intended).

EDIT : Also, was I supposed to hit any button on my graphic card ? I read that there might be a button near PCI-E ports. The only thing I did was double clicking the file and press Y.
EDIT 2 : Do I need to be running Precision X1 to have the benefits of Re-size BAR, or do I always have them, whether I have Precision X1 or not ?