Update:
My card is the ASUS GeForce GTX 750 Ti PH Series (PH is the one with the single fan)
https://www.asus.com/Graphics_Cards/GTX750TIPH2GD5/
and my VBIOS is GTX750TI VB Ver
82.07.25.00.AS11 as shown by the official ASUS GPU Tweak Tool and Ver
82.07.25.00.13 as per GPU-Z.
Question
A lot of people, as I mentioned before, who owned a GTX 750 Ti other than the one made by ASUS managed to get the card working perfectly with the latest web-drivers. A few others, claimed that the issue was with ASUS's BIOS and flashing it with Palit's BIOS fixed the HDMI/DVI issue for them.
I didn't want to actually flash and change my GPU's BIOS so I kept exploring options to load another vendor's BIOS for my card through a bootloader only when Yosemite loads. Unfortunately, I didn't find any comprehensive steps that outlined the process.
I was thinking, maybe, you devs could figure out exactly what is making HDMI and DVI work with Palit's BIOS that ASUS's BIOS prevents and figure out a way to get the ASUS cards working fully with HDMI/DVI on Yosemite?
Maybe a hybrid ASUS BIOS ROM that incorporates only the necessary changes that exist in Palit's BIOS with the rest of the BIOS remaining the same. Is that possible?
If you'd like, I could upload the saved BIOS of my card if you'd like to analyse it or something.