About Sun Fire 480R use freebsd vesion?

[周晔]

Hi,
I have a sun fire 480R,the information is:
Sun Microsystems  sun4u Sun Fire 480R
========================= CPUs ===============================================
                run     E$  CPU     CPU  
Brd  CPU  MHz   MB  Impl.   mask
--- ----- ---- ---- ------- ---- 
 A    0    900  8.0 US-III+  2.3
 A    2    900  8.0 US-III+  2.3
 
I want to know which version can support the machine?
Thanks you very much!