question in hurco vm1 max cotrol

Good evening, I want to ask if I removed the aluminum rack from the machine and then turned it on
(externally) and then found that all the fans are working well including the processor fan but there is no data display on my computer screen, is this normal? If no, Should I install an aluminum rack and connect it to the machine so that I can see data displayed on the main machine screen?

Because in case1(external connection) the orange cables is of course un conected
But in case2 (in machine connection) the orange cables of course shall be connected to machine .

Note : I asked this question because the aluminum rack now In possession of an electronics technician who is trying to repair the peak715 and this the last situation was reached .