Question Motherboard caught on fire, everything working except CPU

[Ezz03]

Hi,

A few months ago, my motherboard was caught on fire, I didn't know what was the reason was, but it appears in an area where VRM is located. So, I thought, I lost all my hardware but when I bought some used motherboard to test all parts, it seems like everything is working fine.

I run a few hours on my RX 470 and looks fine.
SSD, HDD, RAM all working fine. No artifacts whatsoever.

So, this means my CPU dead?
When I turned on the PC with the CPU installed, everything spins but no post. But when I revert back to my backup CPU, everything post and it showed "new CPU installed".

 

[Phillip Corcoran]

It may be the problem CPU needs a later BIOS version or board just doesn't support it.
System won't POST if BIOS or motherboard doesn't support it.

Post full system specs including the CPU that that causes POST failure.

 

[Ezz03]

I already updated the BIOS to the latest version and the bios ver. surpassed the requirements.

broken Motherboard: Asrock B75M
new Motherboard:ASUS P8Z68LX-V (the one won't post)
CPU: i5-2500K (haven't OCed)
backup CPU: Intel Pentium G2020
RAM: HyperX 8GBx2
GPU: RX 470 4GB