I would like to have an Ubuntu 11.04 64-bit test environment. When I try booting the Ubuntu 11.04 64-bit installation CD in VirtualBox, the following message is displayed by VirtualBox:

VT-x/AMD-V hardware acceleration has been enabled, but is not operational. Your 64-bit guest will fail to detect a 64-bit CPU and will not be able to boot.

Please ensure that you have enabled VT-x/AMD-V properly in the BIOS of your host computer.

What am I doing wrong?


  • VBox.logubuntu-test.vbox, and /proc/cpuinfo.
  • Kernel: Linux aux 2.6.38-8-generic #42-Ubuntu SMP Mon Apr 11 03:31:24 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux
  • The Virtualization setting in the BIOS is set to Enabled.
shareimprove this question
Turned out to be a bug in my BIOS. A workaround is available. I'm accepting Chrissss's answer since it should work in most cases. –  ændrük May 10 '11 at 3:34
seriously !! DO not put your solution as a comment !! THank god I noticed your comment :) –  Suhaib Aug 14 '12 at 5:15
add comment

In order to be able to run a 64-Bit system in a VirtualBox, you need a cpu which supports virtualization. AMD calls this function AMD-V, Intel uses VT-x. The Wikipedia explains this quite good. There are a couple of Pentium-4 CPUs which are able to run a 64-Bit OS, but don't offer this VT-x technologie. You can check your system by...

$ egrep '(vmx|svm)' /proc/cpuinfo
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx cid cx16 xtpr lahf_lm
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx cid cx16 xtpr lahf_lm

If you don't get any output, you're not able to run a 64-Bit OS as guest inside your VirtualBox. But don't forget to check your BIOS settings. You might be able to activate these AMD-V/VT-x features inside the BIOS of your computer.

And finally there's a checkbox inside the VirtualBox-Settings. Start VirtualBox, select the virtual machine where you want to run your 64-Bit OS and go into the settings of this VM. Look for "Settings -> System -> Acceleration" and make sure that "Enable VT-x/AMD-V" is activated.

Good Luck :) Christoph

shareimprove this answer
Virtual Box does run 64-bit guests on 32-bit hosts when the CPU can handle virtualization and I/O ACPI is set. –  Takkat May 9 '11 at 17:58
@Takkat, off-topic, but isn't running 64-but guest counter-productive? –  Oxwivi May 9 '11 at 18:04
@Oxwivi: not if you need it to test applications :P /offtopic –  Takkat May 9 '11 at 18:22 
Many BIOSes have bugs related to the enable VT-x/AMD-V setting. That is, they'll say it's on but they'll turn it off randomly (say, after suspend and resume, or subsequent reboots). Check for BIOS upgrades if you have issues. –  neon_overload Apr 27 '12 at 7:12
@neon_overload Is there a way to check if VT-x is still enabled after boot? I suspect BIOS bug ... :( And they don't really recommend to update BIOS here ... –  Augustin Riedinger Feb 17 at 23:00
add comment

Make sure you've selected the 64-bit version of your Linux distribution in the wizard while creating the guest. I had the same issue, but it was solved by setting correct option at "version" of the distribution.

Even when you boot off a 64bit ISO image, it won't run until I set that option (General -> Basic -> Version).

Then you should have the ability to enable VT-x and I/O Apic.

shareimprove this answer
Interestingly this was the answer that helped me. –  Radek Nov 13 '13 at 23:01
add comment

You need to enable the IO APIC to boot a 64 bits OS. At least that is what the docs say, look at the text in the big red square ;).

It doesn't look enabled in your .vbox file:

<IOAPIC enabled="false"/>
shareimprove this answer
Thank you, I should have seen this earlier. Sadly, however, enabling this did not change the behavior of the guest OS. I have since learned that there is an "Ubuntu (64 bit)" preset in which this setting is enabled by default, though. I've updated my question with newer information after recreating the VM using this preset. – ændrük May 10 '11 at 2:18 
add comment

This is an issue only with VirtualBox, to me it is stil a bug. If you install the same OS let's say using the VMWare Player on the same machine it works just fine. Without updatin the BIOS.

Pretty annoying.

shareimprove this answer
I noticed it too. I tried VMWare with 64-bit Fedora and 64-bit ubuntu with no issues. But for VirtualBox it seems to only work with the 32-bit. –  Archimedes Trajano Dec 1 '13 at 7:34
add comment

Enable virtualization in the BIOS.

If it still doesn't work, keep the machine shutdown for a couple of minutes.

shareimprove this answer
I don't understand why I needed to keep the machine shutdown for a while. But it helped. Thx! – lukassteiner May 10 '13 at 15:59
add comment

For an Asus M5A88-M mobo with an AMD FX6100 CPU, the correct BIOS selection is in the 'CPU Configuration' (under the Advanced tab), ENABLE "Secure Virtual Machine Mode" and as already mentioned, make sure VBox "Settings -> System -> Acceleration" and make sure that "Enable VT-x/AMD-V" is activated.

For allowing more than one core with this config you have to unlock the cores in the BIOS (or by pressing 4 at the Asus splash screen), but I haven't tried core unlocker yet.

shareimprove this answer
add comment

I got Virtual Box 4.1.12 with the corresponding extension pack installed on Linux Mint 13 Maya Xfce OS and installed Windows XP Home edition in it.

With a little help from my son I now have the USB's activated. To activate the USB's, press the right Ctrl+Home keys and select Device → Install Guest Additions, run it, it installs a number of things in Windows, leave the 3d box unchecked.

When it restarts Windows make sure it boots up in Safe Mode, log in as Administrator (Windows) then rerun the Install Guest Additions, this time check the 3D box and when it is all done, reboot the session. Shut down the Windows XP session, close VirtualBox, shut down the computer. Restart the computer, restart virtual box, restart Windows XP session, now press right Ctrl+HomeDevice → USB should work, you should see any USB devices connected in the drop down.

I was able to connect my TI calculator (which has very limited functionality in Linux (probably more than my knowledge)). Windows XP in VirtualBox on Linux host PC is the way to go with Windows.

shareimprove this answer
add comment

if you have the capacity then enabling on your BIOS should be really easy, just boot up into BIOS and look for "Virtualization" it should be under "Security". Then just enable. :)

source - http://askubuntu.com/questions/41550/how-do-i-run-a-64-bit-guest-in-virtualbox

'System > Common' 카테고리의 다른 글

ide vs scsi  (0) 2014.07.26
bash - 변수 치환(Variable Substitution)  (0) 2014.05.05
virtualbox - 64bit guest 32bit host  (0) 2014.04.21
ACPI(Adavanced Configuration and Power Interface)  (0) 2014.04.11
X.Org Server  (0) 2014.04.09
Windowing system  (0) 2014.04.09
Posted by linuxism

댓글을 달아 주세요