Problem for replacing a new IDE hard disk and install SCO Unix Open Server 3.0

[Ayman Altounji]

My SCSI hard disk was dead and I now replace a new segate 1.7GB hard disk, I already use compaq utility to detect the hard disk and I try to install Win 98, it's work properly.
After I deleted the Win 98 and install SCO Unix Open Server 3.0, at the "Boot :" prompt I just press to boot from floppy, until I change the N2 (Filesystem) disk and continue to installation, an error occured at the system hanged after the hardware self-check completed, but I can't found the hard disk description in the self-check result table.
After I see the SCO manual, then I reboot and install it again, now at the "Boot :" prompt I type "restart hd=ida0", I can see the hard disk description after the self-check result table but all of the disk parameters are detect to 0, I just ignore this and continue to install. Then after go to the SCO dkinit Menu, I choose "display current disk parameters" and also all the them are 0, I then manually type in the parameters and continue the installation, but an error occured on the "hdinit" process and the system hanged.
Can anyone tell me what is the problem for this case? Is that I need to use the extra command at the Boot : prompt?

Thanks