Boot problem

Hi, guys. I have a OEC 9900 Elite system that doesn't boot up. The C-arm gets stuck after 11 arrows, and the left monitor shows this error message: "SYSTEM ERROR DETECTED X-rays are disabled. Turn the system off, wait 10 seconds, and then restart the system. If this message persists, call for service. Service Information: Vortex IP board is not detected!" I cannot connect with the system using UtilitySuite. When monitoring the booting process with Display Adapter's switch in service mode, it seems that the system tries to erase the flash nodes and reload them, but it fails showing the message "Board firmware validation FAILED!". I reloaded software but the issue continues. All voltages seem to be OK in the passive backplane. I cleaned and reseated all the boards and cables in the rack, visually inspected the Vortex IP board and it seems OK. It does not turn on any LED after booting. I think it could be a defective Vortex IP board but I want to be sure. What else should I check?