If you're using a crossover to your PC, Windows XP will not act as a DHCP server. This still
may work though.
If XP cannot get an IP from a DHCP server, your computer
may be assigned a generic "public" IP. I think these usually start with 64.XXX.XXX.X. This
may be the behavior on the Empeg side as well.
With all these uncertainties, it would be much better to assign your computer and Empeg an IP. Once your network card is installed, go into its properties and then bring up the properties for "Internet Protocol (TCP/IP)". You will need to give your machine an IP address. Use 192.168.0.2. WindowsXP should automatically fill in the Subnet Mask. If not, use 255.255.255.0. See the example below:
In the network properties for the Empeg... Give it an IP of 192.168.0.3 (different than computer) and Subnet Mask of 255.255.255.0 (same as computer). Then, sync the Empeg to save changes. IP and Subnet Mask are the only parameters you need to allow these two devices to talk to each other. Ignore all other fields such as Gateway and DNS servers.
EDIT: You will need a crossover cable to go from your computer to the Empeg.
This is an example of a crossover from CompUSA. It is only $3.42, so it is very inexpensive. There are two standard wiring schemes of Cat5 network cable. You must make sure that you get a crossover cable (not straight).