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There currently is no way to rip HD DVD's on the Mac OSX platform; however, a new problem says it can but people seem to be having problems with HD DVD's. The Blu-Ray side seems to be working.

http://www.makemkv.com/

Handbrake and MacTheRipper do not rip HD DVD or Blu-Ray.
 
Does anyone know how to rip HD-dvds to the computer?

First you'll need an HD DVD drive (won't be in your mac unless you put it there, they never came with them).

Then you can follow Wired's guide for HDDVD to Bluray:

http://howto.wired.com/wiki/Convert_Your_HD_DVDs_to_Blu-Ray

Although the only thing you'd probably need is the AnyDVD HD program (~$110) that they mention, they also list a free alternative, though I've never tried either myself. (They're both Windows programs.)
 
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