Strange no-POST issue with a certain CPU

[Zap]

Just spent some frustrating time messing with parts.

CPU A: Core i5-2500K
CPU B: Core i5-2500K
CPU C: Celeron G530
Mobo A: Zotac H67ITX-C-E
Mobo B: Gigabyte GA-Z68MX-UD2H

CPU A with Mobo A results in no POST. Fans spin but no beeps and no picture. Tried different RAM configurations, re-seating CPU, using IGP or discreet graphics, different PSU. Nothing.

CPU B with Mobo A works just fine.

CPU C with Mobo A works fine.

So, CPU A might be dead, right?

CPU A with Mobo B works just fine.

CPU B with Mobo B works just fine.

(CPU C with Mobo B, didn't bother trying.)

😕

BTW, by "works fine" I mean it turns on reliably and I can get into BIOS. Just bench-testing before I put it into the case. This is why I try to always make sure a motherboard can at least POST before putting it into a case.

 

[Shmee]

that is strange, I wonder if it is a MCH issue with the ram/board on mobo A. Have you tried resetting CMOS, updating BIOS, etc?

If you cant figure it out, at least you could just swap CPU A and CPU B and call it a day; two working systems with 2500K's. 😀

 

[paul878]

Did you mount the cpu when it didn't work?

 

[Zap]

that is strange, I wonder if it is a MCH issue with the ram/board on mobo A. Have you tried resetting CMOS, updating BIOS, etc?

Yes, resetting CMOS. There's a button on the motherboard for that. I tried several times.

No, didn't try updating BIOS.

If you cant figure it out, at least you could just swap CPU A and CPU B and call it a day; two working systems with 2500K's. 😀

That's where I'm at right now. 😎

Did you mount the cpu when it didn't work?

Do you mean the CPU heatsink? If so, yes I did. And yes it was mounted properly, and the fan plugged in.