The default OpenBSD 3.3 kernel has some issues on a DELL Optiplex GX270 that prevent the OS from booting. This seems to be related to a S-ATA controller that cannot be disabled in the BIOS. Please follow the following steps to install OpenBSD on DELL Optiplex GX270, assuming you make no use of the S-ATA controller:
1. Booting from the installation CD
Boot from the OpenBSD CD, wait for the boot> prompt and enter
boot> boot –c
to modify the running kernel. After you get the UKC> prompt type
UKC> disable 50
UKC> quit
which disables the pciide device. In case you are curious, this number is obtained by typing find pciide which would yield output similar to this:
50 pciide* at pci* dev –1 function –1 flags 0x0
Then install OpenBSD as described earlier. Once OpenBSD is installed reboot and wait for the boot> prompt again and enter
boot> boot –c
one more time. At the UKC> prompt then enter
UKC> disable 75
UKC> quit
and boot the OS. The number is 75 now since the kernel installed by OpenBSD is different to the kernel included with the CD. After you have logged in enter the following commands on the shell to write the changes to the kernel (/bsd) stored on the disk: