At the moment I've fully decided I'm making the HD plunge and siding with HD-DVD (despite the digital bits' grim prediction) and am trying to figure out whether to go for the HD-A2 or just the 360 add-on. In the past I had my PS2 as a back-up DVD player and one of the problems with it was that fan noise was sometimes distracting while watching more quiet films. While my current DVD player is silent, I figured the more powerful machine would likely need more cooling, so I was wondering if this was noticable at all.

Similarly, does the 360 add-on make any noise? I thought I remembered hearing that you could use the add-on with the system itself off (is that right?), so I'd be willing to make some sacrifices when it comes to the interface if it means a quiter presentation or a similar presentation with a cheaper price tag.

Thanks in advance to anyone who can help on the matter!

EDIT: Thanks for the help, guys! I just placed an order for the A2.

The Xbox360 is one of the loudest systems I have every heard. The A2 has a fan, but it seems to run fairly quiet. I have it in my entertainment center and don't notice it all while watching movies. I noticed the A1 on quiet scenes, but have yet to hear the A2.

I can not speak for the 360 add-on, but I find the A2's fan to be relatively quiet and no distraction at all.

The 360 add-on itself is almost completely silent -- much quieter than the 360's internal drive, which is ridiculously loud. But there's still fan noise from the 360 when playing an HD DVD and it can be distracting during quieter moments. Unfortunately I'm in a different boat than the others here and haven't heard the A2, so I can't do a direct comparison either.