Windows 10 LTSC has a similar small footprint to Windows 7. Use (requires newer X-series cards – X550 is not officially supported but may work in compatibility mode).
NComputing X550 thin client is compatible with Windows 7 SP1 (32-bit and 64-bit) using the legacy ncomputing x550 software for windows 7
To run an X550 card on Windows 7, you must use compatible vSpace software: vSpace Server X-6.2.7.2 Windows 10 LTSC has a similar small footprint to Windows 7
: Provides vSpace Server X-6.2.7.2 for both x86 and x64 systems. ncomputing x550 software for windows 7