BIOS update???

[kartus]

Hello everybody.
I'm new to this forum. I checked a lot of BIOS forums and this one looked most reliable to get help for my issue.
Honestly I don't know if I'm posting in the right place. I'm not even sure what to write for a thread subject. So I'm really sorry if I'm not doing it right.
With a few words: I recently decided to make a low level gaming PC with second hand parts.
I bought the following MB: Gigabyte GA-MA770T-UD3
Few days later I bought a GPU Saphire Dual-X R9 280X.
The problem is that the MB does not recognize the GPU. According to few forums, a lot of people had this similar problem. Updating their older machines with a R9 280x. Most of them solved it by updating their BIOS to a newer version. Unfortunately my parts turned out to be too old.
The GPU is produced in the middle of 2013 and the latest BIOS for my MB is from the end of 2011. On the box of the GPU it is said that it complies with UEFI 2.3.1 or after, but people are using it with BIOS too.
Is it possible to further upgrade my BIOS, or make it a BIOS UEFI? I'm not really familiar with the BIOS/UEFI stuff, so I'm sorry if I'm writing a stupid question.
The thing is that I can't say for sure that the GPU is working. I bought it 2nd hand (the forum I took it from usually is very reliable) and I don't have friends with new gaming desktop machines to test it on. Everybody I know uses laptops .
Thank You for Your time and your responses in advance.
Best regards, Vlad.
PS: Again, I'm sorry if there is something wrong in my thread.