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8 VBoxManage
• --hwvirtex on|off|default: This enables or disables the use of hardware
virtualization extensions (Intel VT-x or AMD-V) in the processor of your host
system; see chapter 10.2, Hardware vs. software virtualization, page 177.
• --hwvirtexexcl on|off: This specifies whether VirtualBox will make exclusive use of the hardware virtualization extensions (Intel VT-x or AMD-V) in the
processor of your host system; see chapter 10.2, Hardware vs. software virtualization, page 177. If you wish to simultaneously share these extensions with
other hypervisors, then you must disable this setting. Doing so has negative
performance implications.
• --nestedpaging on|off: If hardware virtualization is enabled, this additional
setting enables or disables the use of the nested paging feature in the processor
of your host system; see chapter 10.2, Hardware vs. software virtualization, page
177.
• --largepages on|off: If hardware virtualization and nested paging are enabled, for Intel VT-x only, an additional performance improvement of up to 5%
can be obtained by enabling this setting. This causes the hypervisor to use large
pages to reduce TLB use and overhead.
• --vtxvpid on|off: If hardware virtualization is enabled, for Intel VT-x only,
this additional setting enables or disables the use of the tagged TLB (VPID) feature in the processor of your host system; see chapter 10.2, Hardware vs. software
virtualization, page 177.
• --accelerate3d on|off: This enables, if the Guest Additions are installed,
whether hardware 3D acceleration should be available; see chapter 4.6.1, Hardware 3D acceleration (OpenGL and Direct3D 8/9), page 75.
• You can influence the BIOS logo that is displayed when a virtual machine starts
up with a number of settings. Per default, a VirtualBox logo is displayed.
With --bioslogofadein on|off and --bioslogofadeout on|off, you can
determine whether the logo should fade in and out, respectively.
With --bioslogodisplaytime <msec> you can set how long the logo should
be visible, in milliseconds.
With --bioslogoimagepath <imagepath> you can, if you are so inclined, replace the image that is shown, with your own logo. The image must be an
uncompressed 256 color BMP file.
• --biosbootmenu disabled|menuonly|messageandmenu:
This specifies
whether the BIOS allows the user to select a temporary boot device. menuonly
suppresses the message, but the user can still press F12 to select a temporary
boot device.
• --boot<1-4> none|floppy|dvd|disk|net: This specifies the boot order for
the virtual machine. There are four “slots”, which the VM will try to access from
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