Post subject: [TUT] Set the BIOS clock back in VirtualBox Posted: Fri Jul 13, 2007 2:03 pm
Guru Beta Collector
Joined Fri Aug 18, 2006 12:05 pm
VirtualBox doesn't have great support for changing the BIOS date, but you can set a time offset. While the clock in VirtualBox still synchronises with the host system clock, the clock will be delayed by a certain number of milliseconds. You can use this to set the BIOS clock back a few years, so you can install betas. I tested this with a timebombed Whistler build and it worked fine.
To do this, first open up Calculator. Find out how many days it is between now, and the BIOS date you want. For example if you wanted a Whistler build, a date of 1/1/2001 would be okay. Using a calendar or by using this site you can get the number of days. Between today and 1/1/2001, it's 2386 days.
Now, multiply the number of days by 86400000 (which is 24*60*60*1000) to get the number of millseconds between now and the target date.
Fire up Command Prompt, and CD to the folder containing VirtualBox (most likely c:\program files\innotek virtualbox). Now type:
ou can also do this by editing the XML-file for your VM. Just add this line and edit the value for your matching one:
surround it with the matching XML-Tags.
_________________ "Theory is when you know something, but it doesn't work. Practice is when something works, but you don't know why. Programmers combine theory and practice: Nothing works and they don't know why."
Post subject: Re: [TUT] Set the BIOS clock back in VirtualBox Posted: Fri Aug 21, 2009 11:24 pm
Guru Beta Collector
Joined Tue Aug 05, 2008 8:45 pm
Location Two lefts and a diagonal sidestep from where you are.
Favourite OS Windows 8 Release Preview 8400
On a freshly-created VM, do the following: 1. Download the Batch File from the first post in this post. 2. Run it and follow onscreen instructions. 3. Get an MS-DOS Boot Disk (has to be one with the "date" command), mount it in the VM. 4. Start up the VM, let DOS boot up. 5. At the command prompt type in "date MM/DD/YYYY" (no quotes, Example: 09/21/1999). 6. Shut down the VM, and unmount the floppy image. 7. Done!
Post subject: Re: [TUT] Set the BIOS clock back in VirtualBox Posted: Mon Apr 12, 2010 3:14 pm
Amateur Beta Collector
Joined Mon Mar 29, 2010 2:11 pm
Favourite OS Windows 2000
OMG That is impossible because when you set it on a diffrent time it doesn't apply on a other virtual machine...!
What GuyWithTheDuelDisk said is true, if you set your real machine to the date valid for the beta installation, then start vpc [or the likes], vpc will sync it's time with the machines current time. Though the way the OP posted in the first post is a far neater trick, & saves for when you forget to turn your main machines time forward again.