You need to install the firmware-amd-graphics package. You need to add the following to your sources.list: # contrib and non-free arch:all packages (i.e. firmware) deb [arch=all] http://ftp.debian.org/debian/ unstable contrib non-freeI can see the boot logging until the graphic card initialization, then I have no way to interact. I also tried to load the old kernel (from yaboot menu), but the result is the same.Try booting with "nomodeset".
The good news is that this way works fine. And the suggestion above, fixed the issue.
Then I am going to work on the wireless adapter...
-- Mick