Spreading NIC interrupts across multiple CPUs

[Aaron Seelye <aseelye-lists@eltopia.com>]

I have a question regarding interrupt balancing for a NIC across CPUs. 
I have a Dell R710 (dual quad core) with embedded broadcom 5709 that 
seems to put everything on the CPU0.  I even threw an Intel Pro/1000 PT 
in the Dell, but this is showing the same problem.

For a test system, I have an HP DL360-G5 (also dual quad core) with 
embedded broadcom 5708 that balances across all cores.  I've also thrown 
in an identical Intel NIC, and it seems to balance across the cores 
properly.  This leads me to believe that there's something wrong with my 
BIOS setup, or there's something inherently wrong with the R710, though 
I'm leading towards the former, as I'm seeing this on two R710s, and 
doubt I'd hit a magic breakage across two chassis.

Also, this is with no massaging on my part, both running up to date 
debian wheezy 7.4, with the Dell being installed originally with 7.1

My question is this, what option(s) could be present with the R710 bios 
that would cause something like this to happen?  If not the bios, 
where/what else should I look at?

Thanks,

-Aaron