Must be a patch. DOS didn’t use HLT until version 6 - it just spun instead. https://blogs.msdn.microsoft.com/virtual_pc_guy/2004/12/20/why-does-dos-use-100-cpu

Must be a patch. DOS didn’t use HLT until version 6 - it just spun instead. https://blogs.msdn.microsoft.com/virtual_pc_guy/2004/12/20/why-does-dos-use-100-cpu-under-virtual-pc/ https://blogs.msdn.microsoft.com/virtual_pc_guy/2004/12/20/w...