1 Mpps router and OpenBSD?

[tx]

Is it possible to make 1 Mpps router (BGP and routing between several 
1GBE links) with standard x86 CPU such as Xeon or Opteron and 
"accelerated" NICs like Intel PRO1000/PT? All with latest stable 
OpenBSD, of course :) Any suggestions, tweaks, special techniques for 
that case, any documentation, please?