Before connecting the Ethernet cable, test if the new mainboard has resolved the issue that caused the fault.

Do not connect Ethernet cable at this point, otherwise the printer will not boot.

Connect a PS/2 keyboard and a VGA monitor to the mainboard. Plug in the power cord of the printer and turn it on. The mainboard should beep and show the BIOS logo. It may stop and report corrupted CMOS settings due to the battery replacement in Step 4.

Enter the BIOS by pressing the Delete or F1 key and choose to Save settings, as shown in the second photo. This will save default CMOS settings and the mainboard will reboot itself. It should then boot into the printer firmware, with an ASCII GUI similar to the third photo. The small display at the front of the printer should also function now.

If you encounter any issues, troubleshoot as you would with a regular PC. Check for loose cables/connectors, improperly seated components, faulty power supply, faulty memory, BIOS errors, etc.

The worst problem would be a faulty storage drive since it stores calibration data for valves, rollers, and other mechanical components which were uniquely tuned in the factory. If you need my HDD image from one Zprinter 650 in Acronis, contact me, but keep in mind that it probably won't work well with another printer.