Windows 7 x64 Host - VT-x not recognized

Discussions related to using VirtualBox on Windows hosts.
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WhiteZero
Posts: 6
Joined: 13. Jun 2008, 18:24

Windows 7 x64 Host - VT-x not recognized

Post by WhiteZero »

I'm running a Windows 7 Ultimate x64 host with an Intel E8400 processor. I've double checked to make sure Virtualization Tech is enabled in BIOS. However, VirutalBox does not recognize that I have the feature now that I'm on Windows 7. I've used VirtualBox in Vista x64 with no problems on the same hardware, I could run x64 Guests with no issue.

I've reinstalled my chipset software as well. VirtualBox still refuses to recognize my VT-x hardware acceleration.

I'm using the latest VirtualBox, 3.0.10 r54097

This might be a problem with Windows 7 because VMWare won't let me run 64bit hosts either. Any recommendations?
rasta
Volunteer
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Joined: 24. Jul 2008, 00:25

Re: Windows 7 x64 Host - VT-x not recognized

Post by rasta »

On a 64-bit Windows hosts with processors that support VT-x, does VT-x support need to be enabled in the BIOS?

I am running Vbox on a 32-bit WinXP host now, and VT-x support is enabled in the BIOS. I am about to install WinXP x64 on it. Should I turn VT-x support off when I do so, or leave it on?

I want to run 64-bit Solaris guests.
vbox4me2
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Re: Windows 7 x64 Host - VT-x not recognized

Post by vbox4me2 »

Reboot the Host and go into the BIOS
disable vt-x, save BIOS settings, pause machine after bios boot messages
power down the Host (unplug power cord!)
start the Host and go into the BIOS
enable vt-x, save BIOS settings, pause machine after bios boot messages
power down the Host (unplug power cord!)
Boot the Host.
WhiteZero
Posts: 6
Joined: 13. Jun 2008, 18:24

Re: Windows 7 x64 Host - VT-x not recognized

Post by WhiteZero »

vbox4me2 wrote:Reboot the Host and go into the BIOS
disable vt-x, save BIOS settings, pause machine after bios boot messages
power down the Host (unplug power cord!)
start the Host and go into the BIOS
enable vt-x, save BIOS settings, pause machine after bios boot messages
power down the Host (unplug power cord!)
Boot the Host.
Wow, that actually worked! Thank you, vbox4me2!
Tomo59
Posts: 1
Joined: 19. Jan 2012, 11:12
Primary OS: Ubuntu other
VBox Version: OSE Debian
Guest OSses: Debian Windows

Re: Windows 7 x64 Host - VT-x not recognized

Post by Tomo59 »

Yes, it actually worked for me too !

Thanks vbox4me2
LucasAU
Posts: 1
Joined: 12. Mar 2012, 00:35

Re: Windows 7 x64 Host - VT-x not recognized

Post by LucasAU »

To echo the "me too"'s ... me too. Pulling power for 10 seconds did the trick on a Dell Optiplex 960.
mpack
Site Moderator
Posts: 39156
Joined: 4. Sep 2008, 17:09
Primary OS: MS Windows 10
VBox Version: PUEL
Guest OSses: Mostly XP

Re: Windows 7 x64 Host - VT-x not recognized

Post by mpack »

Those with the "Me Too's" might wish to be explicit about which PC/laptop they are referring to, because it seems clear to me that this "fix" can only be a workaround for a BIOS bug, i.e. flash config changes not being reflected in a RAM copy. Alternatiely, perhaps this happens because the user made BIOS changes but has not reboot the host since (always hibernates). I would like to know if the above rigmarole is actually needed - or would a simply full shutdown (not hibernate) and restart be enough.
zeke009
Posts: 6
Joined: 30. Sep 2008, 16:40
Primary OS: MS Windows 7
VBox Version: OSE other
Guest OSses: Fedora, Ubuntu, Win8

Re: Windows 7 x64 Host - VT-x not recognized

Post by zeke009 »

Quick note for those using an X79 Chipset:

In the UEFI BIOS, version F9 on the Gigabyte GZ-X79-UD3 you have to enable both Virtualization and VT-d. Once those are enabled VirtualBox works fine, enabling just Virtualization will result in an error.

This is found on the BIOS Features tab.
GA-X79-UD3 - Virtualization2.png
GA-X79-UD3 - Virtualization2.png (22.58 KiB) Viewed 29182 times
One other note: Using the Windows based tool to edit UEFI options resulted in corruption for me and required clearing CMOS to resolve. I'm not a fan, so just a heads up on that little gem.
Stuff goes here, but I'd list my machine and not update this for 4 years.
michaln
Oracle Corporation
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Re: Windows 7 x64 Host - VT-x not recognized

Post by michaln »

zeke009 wrote:enabling just Virtualization will result in an error.
What error?
zeke009
Posts: 6
Joined: 30. Sep 2008, 16:40
Primary OS: MS Windows 7
VBox Version: OSE other
Guest OSses: Fedora, Ubuntu, Win8

Re: Windows 7 x64 Host - VT-x not recognized

Post by zeke009 »

michaln wrote:
zeke009 wrote:enabling just Virtualization will result in an error.
What error?
Sorry, I should have grabbed a screenshot. It says Virtualization is available, but not functional. I'll try to recreate the error when I have some time this week.
Stuff goes here, but I'd list my machine and not update this for 4 years.
zeke009
Posts: 6
Joined: 30. Sep 2008, 16:40
Primary OS: MS Windows 7
VBox Version: OSE other
Guest OSses: Fedora, Ubuntu, Win8

Re: Windows 7 x64 Host - VT-x not recognized

Post by zeke009 »

I reset my BIOS to the conditions that this happened in last time and the VM did not through the error. When I had the problem then VM I was using was brand new, I'm not sure if that was part of the problem or not. However, on an X79 Chipset I'd recommend enabling VT options if you get an error about "is present, but not functional".
Stuff goes here, but I'd list my machine and not update this for 4 years.
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