GA-Z97X-UD7 TH boot loop

[Mumbles]

Hi. My friend is building a PC and is having a power cycling problem.
Gone through the usual steps of removing GPU. Removing and swapping stick of RAM. Removing extra HDD. Clearing CMOS with both CMOS button and old school battery method. to no help.
The LED indicator counts to 15 then stops at C0 error which in both online and physical manuals say is reserved.
Any help is appreciated.

[autotech]

C0 CPU status flag test, CPU register test, memory refresh test

Do the lights on keyboard and mouse light up when starting?  If not I would check for bent pins or a bad CPU.