Hello Oliver, welcome to Microsoft Q&A forum.
This is a driver issue, but not the usual Windows Update kind—it's related to your chipset. Your H110 chipset is modern and uses xHCI controllers for all USB ports, while Windows 7's installer was built before these became standard. It's expected when installing an older Windows version on newer hardware like yours.
Your options are:
- Inject USB 3.0/xHCI drivers into your Windows 7 installer using manufacturer or third-party tools.
- Use a PS/2 keyboard and mouse if your board happens to have PS/2 ports (though they're pretty rare these days).
- Update to Windows 11, which support your hardware normally.