brokeassgamer :
delaro :
I would still check your BIOS, it not uncommon for them to start a upgrade with stock on hand. The physical difference between the three boards are literally nothing but changing out the 2 BIOS chips and stamping V1.2,V1.3 or V2.0.
Yup, it's legacy, now I'm unsure xD
Odds are you are not going to get it to work but you could try and return if no luck.
You can try the CMOS clear trick like we use to have to do with hard drives but I doubt you will have luck.
1. Install the new Graphics Card
2. Find the CMOS Jumper.
3. Pull the jumper from the 1&2 position and place the jumper on the 2&3 position for a few seconds, then place the jumper back to the original 1&2 position.
Boot and see what happens, sometimes it works most of the time it doesn't or find a 750 TI since they have a Legacy/UEFI Toggle switch.