X10DRH-CT + 2xE5-2680 v3 not powering on

[vintagehardware]

Moved from a 3u 836 case to a 2u 826 case. And the board no longer power on, either from power button or IPMI. IPMI is running ok. The BMC green led is flashing.
Front panel is connected correctly since I can let the led to blink.
I tried switching power supply and it didn't help. Clearing BIOS didn't help neither. Also tried switching pair of cpus and switching back. Didn't help.
Any suggestions on how to debug further?
TIA

 

[zack$]

Sometimes the stand-offs can short the memory and cause this problem.

 

[vintagehardware]

Yeah, but I was very meticulous about it, making sure that there were 9 standoffs matching the nine screws.

 

[Sean Ho]

it's not too late to pull it outside of case to test, or even temporarily fit it back in the 836. Or at least try with the 836's PSU+PDB. Does anything at all happen when you power it on, e.g., clicking from the PSU, brief fan spin, etc.?

 

[vintagehardware]

Did a motherboard reseat and it still has the problem.
I used to have cpu bent pin on another motherboard but it can still power on. Just no boot.
For this one there is no click or fan spin at all. Which is weird.

 

[zack$]

Can you get into IPMI?

Also did you do any bios or IPMI updates prior?

 

[vintagehardware]

OK I put it back into the 836 case and it's powering on. Since I switched PSU earlier, it most likely is the problem of the PDB on the 826.