Is A09 Bios necessary for installing Vista

Upgrading the BIOS would probably be beneficial for compatibility reasons.  And even upgrading for no reason can still potentially improve things....\

 

Windows Vista has completely changed the sound architecture, so to get the sound card working you'll need to use the Windows Vista drivers for it.

Yes it is necessary. I have the same computer and the AO9 bios is probably the last one we'll see for this model. The Creative beta driver works OK with my Audigy zs, however the gameport does not work yet. I don't care about that, but you might. If so, stick with XP until the drivers come out. Some creative cards will not be getting any Vista drivers, so check that out. The 8400 is kind of borderline for Vista and a newer computer would be better, but it runs fine for me. It evens runs the Aero video with the basic Radeon X300 card.

Make sure you uninstall anything on the Upgrade Advisor Task List--including all Dell Utilities, DLA, all of Sonic, any added utility like Tweakui etc.

The likely reason that your friend's Audigy 2ZS is not being found by the Creative beta driver is because Dell, for a time, was selling their own DELL-ized version of the Audigy 2ZS. This piece of hardware required drivers customized by DELL and wouldn't be recognized by the reference drivers released by Creative Labs.

 

DELL no longer releases DELL-ized audio hardware. The audio cards are now standard reference type and can use reference drivers.

 

Thanks for the support, i appreciate it, i guess i'll be going for A09 when i decide to upgrade vista...