Hi Manik,
not sure it's still an issue but I think it could help to check the Riser Cards. Go and reseat both. Otherwise you need to make a minimal config of the machine.
If you get it up and running, identify the problem by adding part by part.
Please ensure latest level for UEFI and IMM firmware.
This is a "first shoot" and I hope it helps. For more detailed help is not enough information available.
Kind regards,
Ruediger
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Ruediger Zoellner
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