How can I resolve this problem?

Good afternoon, 

I've got an Acer Predator orion 5000, I come to turn the Desktop on and now it starts then resets, and that's all I get from it, I've took the side case off and checked for any loose wires and I can't see to find any, I've check the power lead, took the lead from my monitor and tried that and still the same outcome, I can't think of anything else. 

Thank you