Hello,
Thanks for posting on our forums.
Based on the brief information you provided, I'd recommend using our Service Center product. More information about Service Center can be found here:
http://www.pcdservicecenter.com.
The reason this product would be best suited is because it provides alternative testing methods for PC's that are unable to properly boot. For example on a PC that cannot run it's OS (operating System), Service Center provides a bootable environment via the USB that will load Linux on the system to run full hardware diagnostics. In the event that a system is unable to pass it's POST test, the toolkit also provides additional tools that can help diagnose a PC. For example a Service Center Kit includes a PCI POST card that can help provide the error codes to better identify the failing hardware that is not allowing it to boot properly.
I hope this information helps and please feel free to ask us any other questions.
Best,
Meliton P.