Boot loop?
RE: Vital Signs/Multi-Parameter Report Post

Not sure if any of this can help, but I would first check to make sure the replacement board is fully compatible. Some model monitors have different hardware, firmware, software that may not work or needs updating with your replacement board. I've seen these issues in the past with equipment.
Check to make sure there are no loose wires, grounding straps, boards, etc. Some monitors are very tightly packed. Make sure that the fan(s) are working and it's not overheating.
You may also want to see if this model has a watchdog feature. Check the monitors error log in the service screen for problems.
Make sure the batteries are in good condition. I've seen defective batteries cause many issues with monitors.
Good luck!
Brent SilviusAnesthesia TechnicianBiomedical Sales and ServicesMercuryMed.com
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