mercoledì 19 agosto 2009

Enable Intel VT on Acer Aspire 3810T

the bios version v1.14 enables VT by default. There is no need to use this method anymore.

if the BIOS updater says that your model is not supported, you must roll back to an older update until you find one working. After that update try again.

Following the guide on Feature Enable's blog i was able to make the VT work on the Acer Aspire 3810T. This feature is also called Hardware Virtualization and is usefull when using virtual machines. I'm using Windows 7 RC and it has a feature called Virtual Windows XP where you can run Windows XP inside Windows 7. This software requires that the VT is Enabled. But on my notebook it was not. The cpu has this feature but Acer decided that it should not be available to the user.

You must use the bios v1.08 downloadable at Acer's site. The version v1.10 does not boot from the usb drive.

These are the steps to get the VT feature working on the Acer 3810T:

Before using the tool, you must be warned about the risks and the worst case that can happen.
First the risks (things said last hopefully stick best):- it may not work: simple as that, maybe your vendor decided to go somehow differently about things.
Something else may not work: the laptop still boots, but e.g. Shutdown does not work, or it reboots after a couple of minutes, etc. This could happen if you modified the wrong offset and have been lucky enough to still be able to boot. -> Reverse what you did (if you still know it). Enter the SetupUtility and restore default settings. If strangeness persists, you may need to reflash the firmware (perform a firmware update as usual: This will definitely restore a default VSS).
Now to the worst case: the laptop does not boot - You most definitely strayed from my instructions and touched something that you shouldn't have. Maybe there is a hotkey (Maybe [fn]-[esc], [Windows Key][ESC] or [Windows Key + B] during power-up) to enter a special firmware rescue mode where you can try to restore the firmware (and reset the VSS) from an USB stick -- maybe not. In the absolute worst case, you need to send your laptop in for repair. This could take a lot of time (months), and can cost money. So be warned and don't do anything stupid! :)
If you still want to go ahead, you need a firmware installed where the Setup variable offset has been verified. On Acer 3810T laptops that seem to be always 0x1af.
On to the procedure:
Put this EFI application on an USB-stick that is formated with FAT32 into the following directory:
When the stick is attached to your laptop, it should boot from it regardless of the boot order or whether your allow or deny booting from external devices (actually a security risk of the firmware itself!).
If everything goes well, you should see the following message> Welcome to GRUB!>> Entering rescue mode...> error: file not found> grub rescue>
At first, type:
and press ENTER, a license text should inform you about the risks. More importantly, you should see at the bottom that the tool is looking for the Setup variable and found it. The GUID should match the expected GUID - if it does not, don't continue!
Next, we'll look at the current setting of the VT offset, which is at least on all recent Insyde H2o firmware based laptops that I've encountered up until now at 0x1af.
setup_var 0x1af
again press ENTER and verify that the variable is set to 0x0. Abort if it does not contain 0x0.
The last step is to set this single byte to 0x01 by executing (WARNING: THIS WRITES TO THE VSS):
setup_var 0x1af 0x1
You may verify your changes by executing once more
setup_var 0x1af
This time the byte at the offset 0x1af should read 0x01.
After that you may reboot by pressing [ctrl][alt][del], remove the USB-stick and check with your favorite tool whether VT really is enabled or not.

7 commenti:

Allan MacKinnon ha detto...

Someone should try burning the EFI code to a CD-ROM and then try to boot. Perhaps Acer only crippled USB EFI booting?

Marco "mak" Bettiolo ha detto...

Someone does know if Acer 3810T supports bios downgrading? I can try the EFI cd-rom boot if it is possible to go back to v1.08.

مدونة الأفكار ha detto...

Thanks all thing good
thank you very much for this information .


alonsomh ha detto...

Just downgraded the BIOS and applied the workaround. works like a charm. thanks for the info guys! It is sad that ACER does not expose this setting to the BIOS.

Andrea ha detto...

...non riesco a trovare il bios 1.14 sul sito acer, e l'1.15 non è riconosciuto e mi dice semplicemente che non può esser installato... ...è un problema che riguarda solo me?
grazie mille...

Marco "mak" Bettiolo ha detto...

Ciao Andrea, se non erro ho riscontrato lo stesso problema e la soluzione è stata proprio quella di aggiornare il bios passo per passo tutte le versioni. Mi pare che proprio dalla 1.14 alla 1.15 c'era il problema di incompatibilità del programma per flashare.

Andrea ha detto...

grazie marco, ero riuscito a sbloccare il VT tramite EFI e per il momento resta così.. ..grazie mille per tutte le info, buona giornata.