In brief: Those running an Intel 4th-gen Core processor should know that you won't be able to run DirectX 12-based applications starting with the graphics driver version 15.40.44.5107. As it seems, there's a potential security vulnerability that may allow malefactors to escalate privileges on said processors.
Intel 4th-gen Core processors, aka Haswell, released over eight years ago, received a refresh less than a year later. Despite being relatively old, Intel still supports them in legacy mode.
After finding a potential security issue affecting multiple Intel 4th-gen processors, the semiconductor company announced it would disable DirectX 12 API support to mitigate risks, starting with the graphics driver version 15.40.44.5107. The affected processors include most of the Intel 4th-gen Core processor lineup, including fan-favorites like the i7-4790K and the i5-4690K. The full list includes:
- 4th Generation Intel Core processors with Intel Iris Pro Graphics 5200
- 4th Generation Intel Core processors with Intel Iris Graphics 5100
- 4th Generation Intel Core processors with Intel HD Graphics 5000/4600/4400/4200
- Intel Pentium and Celeron processors with Intel HD Graphics based on 4th Gen Intel Core
Those using a dedicated GPU shouldn't worry, but if you want to run DirectX 12-based applications and games using the iGPU of these processors, Intel states you'll have to downgrade to the graphics driver 15.40.42.5063 or older.
All these processors feature iGPUs based on Intel's Gen7 GPU architecture, but it seems the issue resides elsewhere. Some of Intel's 3rd-gen Core CPUs also use iGPUs based on that same architecture, but they're not featured in the list.