For many years, we ran our Shackleton simulator FS2004 with freeware Aeroworx South African scenery & the Shackleton Project payware model (80% full size to fit on a trailer) Actual seats, yoke throttle quad, pedals etc on an ancient Windows XP tower, with onboard graphics, 4GB RAM, onto a projector (scenery) & 2x screens in the pilot & copilot seats without any issues at all!
Power supply? - No idea.
BTW, after simming (FS2004 & P3Dv4.5) on a laptop (ASUS A15 Windows 11, 16GB RAM, AMD & NVidia GPU, 500GB SSD) I'll never go back to a box - just my own thoughts, after busting my back packing, unpacking & connecting my old box, keyboard, mouse, 2x monitors etc at many of our Virtual Flying club (Cape Virtual in Cape Town)
For me, a laptop just works.