All I can say is try the second bios or run the fans 100%. I know they are loud, and the easiest way to make them quiet is going to be waterblocks, which isn't an option for most people.

I noticed the card would throttle in the mid 50's as well when I tested mine on air.

Voltage really doesn't help Maxwell either way. I don't know why it is, but at ambient temps, the core just doesn't care for voltage increases that much. The colder the card is, the more the voltage increase matters.

Eldaren513

Thanks for the quick reply! The other bios didn't change anything. Do custom bios' change the throttle at all? Water cooling probably isn't logical in my situation since the GPU isn't in a computer case and only the GPU would be water cooled. I can't imagine it would be cheap either. Probably $300+ to water cool this thing. 
If I can't increase that throttle point or remove it, is there anything else I should try to lower temps? Maybe a repaste? Or what about adding copper heatsinks to the backplate via thermal pads? Would that even make a difference? The backplate does get pretty warm.
Thanks!

I don't really think the heatsinks would make much of a difference on the back, and no, watercooling would NOT be cheap at all.  It never is, which is why I stated "which isn't an option for most people." lol.  
 
If you can lower your ambient temps, you can lower your overall temps.  Open a window near your PC if possible, and try to pull some winter air across the card.  
 
There are some slightly expensive options, like the Kraken G10 bracket and AIO setup that will lower the temps, but you need to make sure your whole case has really good airflow and that you can access so copper shims so that you can set it up to work.  That will lower the temps a LOT and give you much better headroom overall.
 
You could try some other bios options, for sure.  I currently have not changed bios on my cards (we are running the same cards, but I am using water cooling and freezing weather air to cool my cards) but a bios swap may help the card out a little. (only change the position 2 bios, never change position 1 for warranty purposes) Just keep in mind that most aftermarket BIOS options are going to be used for watercooling, dry ice and things like that.  A lot of times, these aren't centered around the air cooled users, because these cards honestly were never meant to stay on air.  All of the extra parts that are installed are truly meant for Dry Ice and Liquid Nitrogen cooling, and we just like to keep them on water and air.