I have an old computer with ASUS P5Q Deluxe Intel P45 Motherboard which currently is using GForce 550 Ti graphics card which I gave to my son to play games like Minecraft, Roblox, Gary's Mode etc but recently he get more into more advanced games which require better graphics card.

I have tried to install XFX Radeon HD6870 which I have used few years back but for some reason it did not worked with that mobo (no signal to the monitor).

My question what will be good/max card which can be used with that mobo? There is 750W PSU so it should be fine to handle anything from 5 years back ;)