[TriLUG] SATA/BIOS problem with Linux

[Joseph Mack NA3T]

My son's machine is an Asus mobo with a dual core CPU and 
SATA disk hardware (there is an IDE header but it's not 
used). The machine has a SATA hard disk and a SATA dvd. The 
BIOS has an "enhanced" and a "compatible" mode for SATA and 
it's set to "enhanced".

The machine is currently running winxp and I've had little 
success converting it to dual boot Linux. The following 
distros/live CDs all fail (usually freeze/hang) at some 
stage in booting or installing, all with some sort of disk 
error: Debian, Ubuntu, SuSE (11 I think), Fedora 10. The 
linux based Kaspersky antivirus when detecting the disk(s) 
gets errors like

isw - device for volume "MyRAID5" broken /dev/sda
wrong number of devices in RAID set

While the more commonly used distros hang on attempting to 
install, I can get Slackware to partition/boot/load/install 
just fine and Slackware can mount the winxp ntfs partition 
OK. However the liveCD version of Slackware (Slax) hangs in 
the boot process when detecting the disks, saying something 
like "this shouldn't happen".

If I move the disk to another SATA machine, and boot with a 
linux rescue CD, dmesg detects the partitions (winxp + 
slackware). However /dev only has a single entry for 
/dev/sda (but no sda1, sda2..sdaN). fdisk shows all the 
partitions, but I can't mount them (there being no 
corresponding /dev/sdaN). If I manually add /dev/sda1 with 
mknod, I get "no such device" on trying to mount /dev/sda1.

Even though I can't mount the partitions, I can dd copy the 
disk on the alternate machine and when the copy is moved 
back to the problem machine, the copy boots and runs fine.

The disk which has been initially setup on the "enhanced" 
SATA machine has partitions that don't look right to linux 
(it appears to look like an invalid RAID device). I would 
have thought that Linux would be OK with "enhanced" SATA. 
I'm assuming that I have to look at the disk with dmraid and 
blockid, but I've never used those tools and don't know what 
to look for or how to proceed. I assume I'll have to set the 
BIOS to "compatible" (I assume "enhanced" is causing the 
problem) and then do something (what?) to the disk to make 
the partitions readable to Linux. Will I have to do 
something to make the disk readable to the "compatible" 
BIOS?

Thanks Joe
-- 
Joseph Mack NA3T EME(B,D), FM05lw North Carolina
jmack (at) wm7d (dot) net - azimuthal equidistant map
generator at http://www.wm7d.net/azproj.shtml
Homepage http://www.austintek.com/ It's GNU/Linux!