I asked Asus at CeBit if their elaborate heatpipe arrangements could be used upside down and the answer was yes: you can use any board in any orientation you want. Just FYI: Hopefully this info will be useful for someone who searches.
Interesting. Does this include the heatpipes on older boards, like the P5B Deluxe and P5W DH, or just the newer ones from now onwards?
All heatpipes, I would assume. They're an established teachnology, and there's no real reason to completely revamp them.
Really? there was a thread on this issue back when C2Ds first came out on the xtremesystems forums, and I'm sure a couple of people had problems with the P5B/P5W in upside down cases like the Lian Li PCV1000 I'm using (hence why I did a bit of research into it). Nevertheless, I was cautious, and replaced the heatpipes with a passive Zalman northbridge cooler anyway.
They work upside down because they're fully wicked heatpipes. If they were partially wicked, then they wouldn't. To my knowledge, all motherboard heatpipes are fully wicked.
not all heatpipes work upside down, only wicked ones do. Nowadays almost all are wicked edit: -_- i didnt notic bbq of dooms post.
