This is a SMP i386, FC5, installed box, i'm trying to install FC6 on it.
The DvD I'am installing from has made the sha1sum, the media test,
on a UP box, but won't work on the SMP box.
I also had to use Linux acpi=off at boot:, because of acpi problems.

Error message is:

Ext2-FS:unable to read superblock
isofs_fill_super: breadfailed, dev=md1, iso_blknum=16, block=32
No filesystem could mount root, tried: ext2 iso9660
Kernel panic - not syncing:VFS; unable to mount root fs on unknown-block(9,1}
Time: pit clocksource has been installed.

(and from here box locks up)

You're installing FC6 on top of FC5, not upgrading?

Try deleting the existing partitions. I've found occasionally that installs hang if they find pre-existing partititions.

Well not in case, It was a memory module in a bad slot, moved module to another slot, Found this problem with memtest86.

Jim