other have already given enough information, let me just see whether anything basic is missed out.
just go to RBSU and see whether this controller is selected as default, if not move it as first in boot controller order.
I believe 380G4 is supported for SLES 8 x86 version, so you shouldnt be having any problem.
if you cant find success in it, next method is to check syslog output of SLES installation. we will go to that later if you cant find success with this.
Gopi
Never Never Never Giveup