Supermicro SC836 wouldn't turn on - power distributor (?)

AveryFreeman

ESXi + ( ILLUMOS / ZFS ) = HAPPY
Mar 17, 2017
165
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Near Seattle
averyfreeman.com
Hey,

so I noticed I couldn't turn on my server (which almost never gets turned off/unpluged) in an SC836 case, but the few times I have turned it off / unplugged it for servicing, sometimes it has trouble turning back on and I couldn't really explain why ...

All the cables would be connected, power supplies seated properly, amber lights, etc.

I got the case used and it's been an ongoing issue since I got it.

Then it dawned on me - I'll bet some of the caps on the power distributor are toasted.

Luckily I had another power distributor lying around - but I think it was for a 2U case because the 12v connectors weren't spaced far enough apart to work w/ my backplane (not that big of a deal, there's extension cables).

But I guess my question is -

Anyone had a mystery SM server just not turn on for some unexplainable (without a multimeter) reason? Did replacing the PDB help?

Was this a reasonable assumption on my part, or do you think my computer will fail to turn on next time I try to service it, too?

It was pretty perplexing, I'm glad the computer's working again (for now)

Thanks :)
 

Lost-Benji

Member
Jan 21, 2013
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The arse end of the planet
They hate humid air. Blow the PSU's and backplane out completely with compressed air. Then use a hair-dryer on low heat to blow through the PSU's to warm them up. Keep your hand in the air stream before them (after the hair-dryer) to ensure the air is warm and not to hot. Once they are warm, turn of power, amber lights on rear and fans should ramp down to dull roar. Now turn on system.

Otherwise, if you know that your PSU's are good and clean of dust, connect power for an hour or two and try later. Standby power lets them warm up.
 
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AveryFreeman

ESXi + ( ILLUMOS / ZFS ) = HAPPY
Mar 17, 2017
165
19
18
39
Near Seattle
averyfreeman.com
They hate humid air. Blow the PSU's and backplane out completely with compressed air. Then use a hair-dryer on low heat to blow through the PSU's to warm them up. Keep your hand in the air stream before them (after the hair-dryer) to ensure the air is warm and not to hot. Once they are warm, turn of power, amber lights on rear and fans should ramp down to dull roar. Now turn on system.

Otherwise, if you know that your PSU's are good and clean of dust, connect power for an hour or two and try later. Standby power lets them warm up.
That's an interesting process. Sounds helpful.

I noticed the computer did have to "warm up" the few times I'd experienced the issue. Seems further indicative of a cap that's not adequately storing electricity.

So glad I had that PDB to throw in it.
 

AveryFreeman

ESXi + ( ILLUMOS / ZFS ) = HAPPY
Mar 17, 2017
165
19
18
39
Near Seattle
averyfreeman.com
Had the exact symptoms with a 216 chassis. Replacing the PDB sorted out the issue.
YAY. Yeah I've had to do more maintenance on it since then and with the new PDB the server fires right up.

It's almost like I don't have to writhe in terror every time I have to shut it off anymore.

Server not turning on is a concerning experience to say the least.
 

RageBone

Active Member
Jul 11, 2017
296
77
28
had the case that a SM x9drif stopped linking a particular PSU.
Since that PSU worked in another machine, it had to be the board and i got for cheap.
Turned out to work with another PSU just fine.