Incorrect number of CPU detected (Windows 2003)

[SGorodskoy]

Virtual Box 4.3.14 r95030 allows setting maximum of 2 CPU per virual machine (even that with error "Invalid setting detected").

I have i7-4930K processor with 6 cores, 12 in windows w/HT, so there should be 12-24 available cores in VBox as i can understand.

[SGorodskoy]

Test machine log

[SGorodskoy]

Screenshot of guest config System-Processor tab

[Frank Mehnert]

Indeed your processors has 6 physical cores with 2 hyperthreads per core. To detect the number of physical cores we use the GetLogicalProcessorInformation(). Unfortunately this function returns the number of processors, not the number of processor cores under Windows 2003, see ​here. I think we should fallback to the old way for Windows 2003.

[Frank Mehnert]

Actually there is also a Microsoft hotfix available for this problem, see ​here.

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.