swapping out mb and cpu

[je killen]

Hello;
I have a machine running with FreeBSD 6.0 running on AMD64 socket 754 
and Elite Group motherboard. It has been up and running without problem 
continuously for about 5 weeks now (although I am the only one 
connecting to it at present). I have purchased
a new mother board and cpu. The new mb is Gigabyte GA-K8N-SLI and the 
new cpu is Athlon 64 socket 939. It has extended PCI slots and I am 
planning on swapping the FreeBSD installation to the new motherboard 
and processor. If I just move the hard drives
and SCSI adapter to the new machine will it run on the different 
motherboard and processor? Or do I have to install FreeBSD specifically 
on the new machine?
  The reason I'm considering this is because the AMD64 754 machine has a 
SCSI adapter made for an extended PCI slot.
The mb has only standard PCI slots so the adapter isn't being used 
optimally.  So I would be swapping the main drive (ata) and two SCSI 
drives (assigned usr and var partitions, respectively), as well as the 
adapter.
Is this possible?
Thanks in advance;
JK