HP has no ethernet driver posted for this model:
http://h10025.www1.hp.com/ewfrf/wc/s...uct=94088#N156
Please open Device Manager, find and double-click the hardware device you need a driver for, click the Details tab, select "hardware id" and give me the hardware id string that begins with "PCI\VEN", (1st./top line of text only).
Note: If no driver has been installed for the network controller, it may be listed under "Unknown Devices".