Thanks for the info
VT-x improves virtualisation support for intel processors (check for "VT-x" or "Vanderpool" or "HAV" technology or something similar in the BIOS)
x86 virtualization - Wikipedia, the free encyclopedia
It's just used by Vbox and seen in the acceleration tab.
I think your system (as seen in yous specs here on site) has VT-x
But VT-x is not really required.
It will make your VM work faster, that's all.
So the real problem is the graphic acceleration. Virtualbox installs the VDDM driver for 3D support by default in the latest versions and it's a buggy driver and still in developpment. The screen flickering it's normal (i'm serious). They still fix crashes for the aero interface but with the latest version (Vbox 4.1.16) the glitches got worse.
If 3D is enabled, Vbox installs VDDM driver by default.
It will work after some change of settings but the 3D gaming and acceleration is still unstable and metro apps can crash, but there is basic support and you can mount shared folders and auto-resize the screen.
Install the latest Virtualbox (now 4.1.16) from https://www.virtualbox.org/wiki/Downloads
and the extension pack (for usb 2.0)...
If you already use the latest version:
Go (in the Win 8 VM) to System -> Advanced system settings -> Settings -> Adjust for best performance
You can the enable some features like this:
It' s better than the standard settings with animations (standard settings will work bad on Vbox => especially with 4.1.16)
Then install the additions in your virtual machine (leave 3D acceleration enabled if you still use 256mb) -> try with 128mb because the VM still uses limited support without dedicated memory (like in the case of VMware Player 3D)
Reboot and it will work nice (the flickering should be gone by now).
Some flickering it's still possible due to the driver's status but should work pretty good (works for me in Vbox 4.1.16 on Win7 x64)
If it still flickers badly (or constantly) try disabling 3D in Vbox settings and remove the VDDM (Vbox display adapter) in the VM's Device Manager (Drivers)
the reboot the VM without 3D support.
I'm using the VDDM (3D support) because it 's getting better and better and after applying the fix i've mentioned it should work without flickering.
Don't use applications that mostly require 3D on Virtualbox because there are limitations (3D support is still experimental and crashes and lacks in performance are daily issues)
I think it's clarified by now. So the flickering is normal with the current Vbox drivers (look always for newer versions of Vbox and the chance is they fix some 3D support a bit). Try the fix with the Performance Options as sen in screenshot above.
Sorry if I wrote too much in this post but it should work (with 3D support or not).
Good luck with the installation.
I recommend to leave the 3D support on in Virtuabox because Win8 uses it.
If by chance the 3D support could not be disabled in Vbox (above version 4.1.10) leave it on and just uninstall the Virtualbox Display adapter in Device Manager in the VM.
Then you will use the Microsoft Standard Display Adapter (with basic 3D support). => Automatic screen resize is not possible with this driver.
If VBox WDDM works, don't uninstall it!
This fix was seem in some posts here on the forum as of version 4.1.12 of Vbox the 3D support could not be disabled anymore for Win8 in VBox.
Without the WDDM driver you are limited in the display resolutions you can use. Usually these are 4:3 aspect ratio. You can add other screen resoutions by editing the .vbox file in a text editor (I use NP++) and add your own. You need to locate the ExtraData section and add the top line of code found here.
The values are width,hieght,color depth. This only takes effect if the WDDM driver is not used. This will then appear in the Windows screen resolutions. You can have more than one just replace the 1 with 2 etc. This isn't the official way of doing this which is using VboxManage but it works.<ExtraData>
<ExtraDataItem name="CustomVideoMode1" value="1366x768x32"/>
<ExtraDataItem name="GUI/Fullscreen" value="on"/>
<ExtraDataItem name="GUI/LastCloseAction" value="powerOff"/>
<ExtraDataItem name="GUI/LastGuestSizeHint" value="1024,768"/>
<ExtraDataItem name="GUI/LastNormalWindowPosition" value="8,27,1024,687"/>
<ExtraDataItem name="GUI/LastScaleWindowPosition" value="122,108,1128,608"/>
<ExtraDataItem name="GUI/MiniToolBarAlignment" value="top"/>
<ExtraDataItem name="GUI/SaveMountedAtRuntime" value="yes"/>
<ExtraDataItem name="GUI/ShowMiniToolBar" value="yes"/>
VirtualBox allows up to 16 custom resolution so make sure not to exceed that number.
I've added these 16:9 known resolutions (in 32bit color) just in case:
1440x900 is actually 16:10<ExtraDataItem name="CustomVideoMode1" value="800x450x32"/>
<ExtraDataItem name="CustomVideoMode2" value="1024x576x32"/>
<ExtraDataItem name="CustomVideoMode3" value="1280x720x32"/>
<ExtraDataItem name="CustomVideoMode4" value="1440x900x32"/>
<ExtraDataItem name="CustomVideoMode5" value="1920x1080x32"/>
TIP: you can even use the large HD resolutions on smaller screens using VirtualBox Scale Mode.
It will probably look messy but at least you can get the feel of a larger screen resolution.
Shon John Xander
yes.. i got it.. Thank you.. So i can set my desired resolution in that?
Yes you can. With the caveat that it only works when the experimental 3D WDDM driver is not installed, which I think fits your case.