Incompatibility between PSU and motherboard?

[foogitiff]

Hi,

I got a 2U chassis with a dual Delta 550W platinum, and a AC-171A DC power distributor.

I tested the PSUs on the following motherboard:

• Asus Prime X470-PRO (no BMC)
• Supermicro X10SDV-6C-TLN4F (with AST2400)
• Asrock Rack WC621D8A-2T (with AST2500)

All these mobo work fine in the chassis.

However, a Gigabyte MC12-LE0 does NOT work. The BMC won't even start. The CPU fan does some kind of "twitching", and I can here some clicking. No boot.
When I use an ATX PSU Corsair 850W, everything work.

I never encountered an incompatibility between a motherboard and a PSU?

I don't find any info on the power distributor, not sure if I can update the firmware on this thing.

Any idea?

 

[i386]

What chassis?
Is it the same when testing with the other psu?

 

[foogitiff]

It's this chassis: Textorm TXNC2U65-8H2P - PC cases - LDLC 3-year warranty

I tested the other PSU with this motherboard outside this chassis, but I tested the other motherboard inside the chassis.

 

[nexox]

Sometimes that's how a PSU behaves when there's a short and it immediately hits over current protection on start. Is there a chance the Gigabyte board has a mount hole in a different position and you left an extra standoff under there?

 

[foogitiff]

That's the first thing that came to mind, I also tried the Gigabyte board outside the chassis (but with the PSU), same behavior.

Here is the result:

http://imgur.com/a/d6yS7qQ

(yeah I forgot the CPU 12v connector, but the behavior was the same with or without it)

 

[i386]

I'm not sure why the fan is moving at all.
Is the board set to always on in the bios settings?

Does ipmi work when the delta psu is connected?

 

[foogitiff]

Nope, the board doesn't start automatically on the other PSU.

IPMI doesn't start when plugged to the delta PSU, the BMC led doesn't even light up.

 

[nexox]

Perhaps that board requires more current on the 12V Standby pin than your Delta PSU can supply? I'm pretty sure that's the one which runs the BMC while the system is off.

 

[foogitiff]

If I compare the data on the PDU sticker vs the Corsair specifications, it should be fine... I tested board with AST2400 and AST2500 without issue.

	Delta 550W + PDU	Corsair RM850x
+12V	42 A	70 A
+5V	14 A	20 A
+3.3V	10 A	20 A
+5VSB	4 A	3 A
-12V	0.5 A	0.3 A

 

[nexox]

Right, 5V standby, not 12V, hadn't had enough coffee yet. In any case I'm stumped, but the lack of BMC seems like a place to start looking, perhaps measure the voltage on that pin while it's plugged in, or depending on how much equipment you have, try powering just that pin to see if that gets you BMC while monitoring current.

 

[foogitiff]

So I compared the reading with a cheap ATX PSU tester from Amazon, the Corsair and the Delta PSU seems to have close values (but it's not under load, except for the Delta PSU that still power the backplane).

The only difference is on PG: 120ms on the Corsair vs 380ms on the Delta. Both values should be within specs (but the tester seems to think that the Corsair value is too low).

 

[Heisenberg]

Did you try only using one ATX12V 4-pin instead of two?

 

[foogitiff]

Just tried, same behavior with none, 4, or 8 CPU12V.

 

[nexox]

This still feels like a short to ground, even though you've done enough experiments to eliminate that. If you have a volt meter can you probe the 5VSB line while everything is plugged in, when the BMC should be running?

 

[foogitiff]

I have a volt meter, but I am not sure how to probe the 5VSB, should I try to follow traces on the PCB comig from the ATX connector?

 

[nexox]

You can usually fit a probe in next to the wire in the back side of the ATX connector, you can do the same with the other probe for ground or just hit the shield of an ethernet port or something.

 

[RageBone]

i agree with nexox here, sounds like the delta is somehow struggling to supply 5VSB to the giglebyte.

And you should be able to measure into the 24pin ATX as he described. Unless you have probes as thick as your fingers ; D

 

[kapone]

Permutations and combinations...

Connect the Delta PSU to the Gigabyte motherboard with just the ATX and EPS/CPU connectors. No front panel wires, no USB devices, nothing.

See, if the BMC comes on.

 

[foogitiff]

I tried every combinations… ATX only, EPS only, without CPU, without ram, ect. The C never start.

No issue with the same PSU with a WC621D8T. Haven’t had the chance yet to measure de 5vsb

 

[kapone]

I tried every combinations… ATX only, EPS only, without CPU, without ram, ect. The C never start.

No issue with the same PSU with a WC621D8T. Haven’t had the chance yet to measure de 5vsb

Inspect the ATX connector on both PSUs. See what's different.