I'm going to say at the start that I might be completely wrong about this. (And I may be confusing FC4 with CentOS.) But are you sure you aren't needing the megaraid.ko driver rather than the megaraid_mbox? Not sure about install time, but for boot time, mkinitrd gets this wrong and I have to go in and copy the proper module (which is not in kernel/drivers/scsi/megaraid, but in kernel/drivers/scsi) into the lib dir of the initrd and then add: insmod /lib/megaraid.ko to the init script in the initrd. Anyway this link *might* be of help: http://www.tuxyturvy.com/blog/index.php?/archives/4-Installing-RHEL4-on-Systems-with-Legacy-Megaraid-Drivers.html But have you considered the possiblility of using software RAID? After all the problems (along these very lines) that the legacy PERC cards have caused me, I'm moving my servers to software RAID. It depends upon your specific situation, of course, but it makes sense to consider the possibility. For example, hardware RAID5 might be better if disk performance is critical, as RAID5 has a lot of processor overhead. But for, say, RAID1, software RAID has some advantages. -Steve