Problem installing 5.1

[Anders Lind]

Hello friends,

I have been using FreeBSD 4.7 at work for some time now and I want to 
use it at home as well, but I get the following error message when I want 
to install it, this in kernel booting sequence on mfsroot floppy.

DMA LIMITED to UDMA33, non ATA-66 device or cable
acd0: read data overrun 34/0
MODE_SENSE_BIG command timeout
resetting device

Somebody that can give me a push in the right direction

TIA

/Anders