What game and what brand and model graphics processor does your machine use ?
Assuming your graphics drivers are installed ....
What matters with games is what DirectX versions your graphics card can use. This can be found in - dxdiag - Display tab > Features Levels.
(R\click on the Start button and type dxdiag into the Run command)
Most people get confused about DirectX because they look at the System tab in dxdiag, or other places that show
the highest version of DX Win10 can use.
Thing is... Win10 is the only Windows that can use DX12, but it has files for DX9,10 & 11 as well. If it didn't the vast majority
of games would not run on Win10.
It's not really about DX12 backwards compatibility.
The different versions of DX are all different files and effects, with DX9 being the least advanced graphics effects of the four (9,10,11,12).
Look in System32 and you will see many DX files for each version of DX. (including one for DX8. Win10 can also run DX7\8 games, btw.)
The game selects which DX files it needs, not Windows.
Win7 was similarly labeled as DX11 compatible, but was also compatible with DX7,8,9 & 10.
Just to complicate things further. MS decided that DX11.1 is a low level DX12, making a DX11 gpu DX12 'compatible', but
DX12 games require a gpu that can use DX12.0 & DX12.1. So for gaming purposes... not!
True gaming DX12 capability starts with AMD HD7000 series and Nvidia GTX900 series.
I don't know which AMD integrated graphics are DX11 or 12, but Intel HD4000 is the first DX11 Intel integrated graphics.
I believe Intel UHD is the start of DX12.
- Similarly a graphics processor with DX10.1 is said to be compatible with DX11 (Intel HD2000\3000), but it is not compatible with DX11 games.
- Some games use DX9 effects with their low settings and DX10 or 11 with the high settings. Some newer games no longer use
DX9 but use either DX10 or 11. Or 11\12, or just 12.
The game that has caused the most confusion is Fortnite. Until about a year ago Fortnite ran on DX10 & 11 effects but at some
point in time (I don't recall the name) they introduced a new season that uses only DX11 & 12 effects.
- Lets make that a bit more (or less) complicated.
If you have a graphics processor that is DX11 capable, but it does not meet the processing power requirements of the game
in question, you will often get an DX error when trying to run the game.
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