Then your problem is clear. You have a BIOS bug.
Dang... Ok, that's something we can deal with.. have to go hunting on the MSI site for a new BIOS and flash it. My brother can do that... I hope :-)
sata controller BIOS). Explanation: The EDD code calls into the BIOS before the kernel enters protected mode, so if that call hangs, your machine will not boot.
Interesting.. that's good to know...
Hm, is your computer by any chance manufactured by Fujitsu-Siemens?
Nope. It's a "home built" system, assembled from various individual bits.
Did I understand correctly that you can boot into Linux with SATA enabled and edd=off? If not, can you find a pattern when Linux with SATA works, like only the first time after switching on the machine, or only if no CD/DVD was in any drive or something like that?
I tried listing all the combinations we've tried... but I have ot check again with my brother... just to be sire... so I'll try to follow up on this later. We do have a fairly repeatable pattern where Linux will boot initially (without the edd=off param), but if we enable SATA at any point and boot to Windows, then disable SATA and try to boot Linux it's dead, and remains dead. only a reinstall seems to "resurrect" it again. Using edd=off, and with SATA enabled, we were able to get it working, but there were still intermittent boot problems - sometimes it will take 3 or 4 tries to get Linux to boot. We will try a BIOS update, and I'll try to get a complete list of the combinations we've tried and results... C.