Thank you for your question and reaching out. I can understand you are having issues related to Windows performance while running QT.
- Disable any Antivirus program or Windows firewall you may have for temporary purpose.
- Cleanup below Temp folders
- Run Disk Cleanup from Select C:\ Drive from Properties- > General -> Disk Cleanup - >Cleanup system files
- Run sfc /scannow
- Run below DISM commands from elevated prompt.
DISM /Online /Cleanup-Image /CheckHealth
DISM /Online /Cleanup-Image /ScanHealth
DISM /Online /Cleanup-Image /RestoreHealth
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