aic7xxx/FreeBSD/Linux can't find disk drives

[Matt Bjornson]

I have a Dell PowerEdge 2400 with dual 733 Mhx CPUs.  I have tried to 
install  several distros of Linux (Red Hat 9.0 and Gentoo 1.4) and 
FreeBSD 4.8, 5.0 and while I can get the kernels to recognize the 
Adaptec 7890 and the Adaptec 7880 and use my scsi CDROM, when I fdisk 
to try to create partitions, I receive a unable to find /dev/sda
Thanks