Installing FreeBSD from USB CDROM drive

Thu Feb 28 05:04:06 UTC 2008

I am having problems installing both 6.3 and 7.0 using a CDROM drive that
plugs into a USB port.  The boot process starts, then I get scrambled text
over the whole screen scrolling like crazy.  I can't read any of it.

I have no such problems booting or installing from other CDs on this same
computer.  Ubuntu 6.06 installs just fine, and System Rescue CD 0.4.2 boots
up just fine.  Any ideas?