I have the same problem, I have a
ASUS P5B
2 X Raptor 150 in raid0
a WD 250GB
a DVD-RW samsung SATA
and yesterday i got the Plextor 760SA

i plug it in one of the 6 sata ICH8 all ok till i installed the plextools tha freeze my pc on startup i had to start windows in setup-mode and remove it from startup !

I then try to use the other sata far away from this six, in an horrible place just under my VGA card. In the Bios i set in IDE mode and now the plextools work... but I don't like this solution, I bought a very expensive burner SATA and I have to run it in IDE mode ???

Hope that Asus/Intel/ or plextor come out with a solution to this.

Bye