Way noob!

I'm having a problem getting RH 9.0 loaded and booted onto an Intel Entry Server Board (S845WD1-H) based system.

The drivers included with the motherboard indicate they are for RH 7.3 and 8.0. After some searching, I downloaded a compiled set of drivers for 9.0.

My issues begin with whether to configure a RAID array at the controller chip; when I do configure an array, the Red Hat install process doesn't find a disk (this is after specifying expert to the boot: prompt and loading the driver).

Deleting the array at the controller allows the installer to find a drive, which it calls hdc, and the installation proceeds to completion. I Ctrl-ALT-F2 at the congrats screen and follow the driver installation completion procedure, exit and reboot.

The system finds no bootable units and stops. In fact, without an array defined at the controller, I can't configure the boot order for the hard drives in the bios.

What the heck am I doing incorrectly?

You need to configure the array then start the install process. Don't use the software raid options shown in the redhat installation.