I cant seem to saturate my gb network!

I am getting realllllly bad performance out of our new iscsi system..

15 disk raid6 on a 3ware 9650 with BBC = 94mb read, 9mb write.
http://www.3ware.com/KB/article.aspx...2&cNode=1R6H2L (this is the document for benchmarking im using)

our server is supermicro 836-tq with X7DBE+ mainboard and 500gb seagate drives with NCQ enabled.

Any ideas?

If i wanted to tune some settings (receive descriptors for example) for my e1000 driver.. is there anyway i can do this?

http://www.intel.com/support/network/sb/cs-009209.htm

thanks in advance for any insight!