Do graphic cards that support DX 12, support all previous versions of DX or is there a cutoff?

[LOST TALE]

Do graphic cards that support DX 12, support all previous versions of DX or is there a cutoff?

[Cyracus]

full backwards compatibility

[8tg]

They’ll run all older versions of DirectX though there are other software limits that keep a card like say, an RTX 3090 from properly playing games from something like the DX7 era *sometimes*.
Some older games won’t have any idea what to do with a modern gpu, but can sort of brute force themselves to run “in the blind” so to speak.

 

Example, older versions of Halo: Combat Evolved, don’t understand any modern gpu after about the nvidia 8000 series. And they’ll ask to run in compatibility mode but if you opt to ignore that it’ll just use any resources they need unless the game is using something where it would run out of resources.

For a specific example on that, Halo 1 will error if you have a 750ti, but it’ll run flawlessly maxed out on a 750ti because everything it needs is there. However it also doesn’t know what intel HD3000, Sandy bridge igpu, is at all. So it’ll run on HD3000 but if you’re vram is limited to say, 128mb, it’ll hard crash when it uses 129mb because it doesn’t know what’s there or what it can use.