Help!

Im building a test enviroment and I cannot get NetWare 6.0 to apply Service Pack 5 with out breaking it.

Im installing to a Dell GX270 3.0 Ghz with Hyper threading disabled, install of Netware works fine, but as soon as I apply the SP it dies after the reboot.

I have tryed not intalling driver updates, and manualy preforming the reboot to no avail.

What have i done wrong?