I just read the manual (I don't even own this switch!) it says that under the STP you can explicitly set a port as edge. (only for ports that connect...
are you using full sql? if your using the express it's limited to 2 cpus and 2gb of ram usage? (I think) you need full sql if you want to beef it up....
Have you tried disabling some of the hardware accelerations on the NIC? (flow control, arp offloads, tcp offloads) I find this helps if the driver is...
the hp storage server runs windows server? what os is your workstation? Do you get poor throughput if you copy a file from the storage server? Reboot...