[Click] Changing NIC parameters for improved click performance

[Latency Buster]

Right now, I am getting huge number of drops at the NIC rx buffer.. at
500bytes at 300Mbps.. The rx ring is at 4096 and I am using PollDevice
(..., BURST 64,..).

1. Is  there a way to increase the rx buffer on the NIC? (intel
82546EB) [somewhere is e1000_defines.h?? or better via ethtool?]
2. I would like to balance the click threads on cpu 2 and cpu3 (as
seen in /proc/cpuinfo). I changed the StaticThreadSched (fd0 2, td0 2,
fd1 3 td3). But when I use ./click-install -t 2 --cpu=2 <config> I get
a warning which says that '3' is out of range or something similar.
3. I have two dual port cards but I need only two links. Is it better
to have input and outgoing links on separate cards?

Thanks..