My last post was based on my experiences with wireless network printer sharing. After rereading your original post I realize you never mentioned printing over an AirPort network.
Perhaps something simple but overlooked is your fly in the ointment. Did you go to Applications > Utilities > Print Center? Your printer should be listed there, and if not that could be the problem. I checked Apple's Printer Compatability List and the 970 is listed, but no mention of the JetDirect 300X 10/100 Print Server. HP's page for the print server makes no mention of OS X compatability either.
Perhaps you could try networking the printer through your Mac without the JetDirect unit? Worth a try, and if you're not networking wirelessly it just might work.
Perhaps something simple but overlooked is your fly in the ointment. Did you go to Applications > Utilities > Print Center? Your printer should be listed there, and if not that could be the problem. I checked Apple's Printer Compatability List and the 970 is listed, but no mention of the JetDirect 300X 10/100 Print Server. HP's page for the print server makes no mention of OS X compatability either.
Perhaps you could try networking the printer through your Mac without the JetDirect unit? Worth a try, and if you're not networking wirelessly it just might work.