I am interested on this too. Even if you don't mind, do you mind to share with me how to install el capitan on this MB, bios config...a simple tutorial....??
I am on Mavericks and I am not able to update to El Capitan in a new installation.
Thank you in advance.
I have exactly the same problem. The same card but different monitor, DELL P2715q
I don't know what is exactly happening but....I have distorsioned the right side of the screen, at the border.
Can anybody help me?