Something may have gotten loose in transit. Could be a minor that may be easily remedied.
What exactly do you mean by 'system has failed to boot up'?
Is the power supply switching on at all? Is the CPU fan running? Is it hanging at any point during boot?
Disconnect main power cable, then open the case & have a look that ALL internal cables are secure/well-connected to the components, & that everything (graphics card, RAM, etc) is slotted in well.