Can't select more than one CPU in 3.0.0

Discussions related to using VirtualBox on Windows hosts.
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MojoHand
Posts: 2
Joined: 30. Jun 2009, 23:54
Primary OS: MS Windows XP
VBox Version: VirtualBox+Oracle ExtPack
Guest OSses: Fedora 11, openSUSE

Can't select more than one CPU in 3.0.0

Post by MojoHand »

In the Settings->System->Processor tab I can't set it to present more than one cpu to the guest. The slider won't move and the text box is grayed out. I have a four-core host. What am I doing wrong?

Much thanks,
Mojo
TerryE
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Primary OS: Ubuntu other
VBox Version: VirtualBox+Oracle ExtPack
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Re: Can't select more than one CPU in 3.0.0

Post by TerryE »

You need to install an I/O APIC + SMP kernel. The old one was probably a single core kernel. Also note that this might trigger windows reactivation.
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MojoHand
Posts: 2
Joined: 30. Jun 2009, 23:54
Primary OS: MS Windows XP
VBox Version: VirtualBox+Oracle ExtPack
Guest OSses: Fedora 11, openSUSE

Re: Can't select more than one CPU in 3.0.0

Post by MojoHand »

Install it where, in the guest? My host(WinXP) can see and use all four cores already.
TerryE
Volunteer
Posts: 3572
Joined: 28. May 2008, 08:40
Primary OS: Ubuntu other
VBox Version: VirtualBox+Oracle ExtPack
Guest OSses: Ubuntu 10.04 & 11.10, both Svr&Wstn, Debian, CentOS
Contact:

Re: Can't select more than one CPU in 3.0.0

Post by TerryE »

Sorry misread your post. Your guest needs an SMP aware kernel. Your host CPU needs VT-x / AMD-V support. You can't do SMP without it.
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