New to me, ML370 G4 - Powered off noise

[RSextonFL]

Hello all,

I have searched the boards and not found what I was looking for so here I am (again (I have another tread going))

  I have picked up a ML370 G4 and when the power supplies are plugged in (either or both) I have what sounds like fan noise running while the server is powered off.  The only way to stop the noise is by removing power to the power supplies.  If I turn the server on, of course it does it's think and everything fires but calms back down, yet the running server overpowers the noise heard when the server is shut back off.  Either manually wiht the switch or virutally with the ILIO acess.

  I have never seen this before and wondered if this was by design, but have not found anyone else asking the same question and therefore no longer think this is by design.

  Does anyone have any knowlege about this and if not by design, what I could do to stop it?

Thanks,

Robert

[Suman_1978]

Hi,

Have you figured out where the noise is coming from, is it from the power supply fans or system fans.

My guess would be system fans, see if any fans are missing.

ML370 G4 has 6 system fans, in which 1, 3, 5 are primary fans and 2, 4, 6 are redundant fans.

Thank You!

I am a HP employee.

[RSextonFL]

Sadly, I have not found the exact source of the fan noise while the server is powered off.  I can say, it is not coming from any visible fans with the lid off from inside the server.  Where I have this located right now, there is not much chance of any valid air flow, and by using my hand only, it does seem air flow is coming from inside the power supplies.  Both of them.  This is far from a little hum, as it's downright fan noise, and the server is powered off.  Due to the server noise when powered on, I can only assume the noise is still present, but overpowered by the server itself.

  I have personally never been exposed to any server that has running motors or fans during a power off state.  My Rear Projection TV does until the bulb cools, but never until now, a server. 

 I would love for this to be by design, but I struggle with that.  Likewise, I don't yet have any spare power supplies, but if I did I sure would test with that.

  Is there any other reason I should be hearing this while powered off? 

  Thanks!

  Robert

[gregersenj]

It's by design.

Just to make sure, I testet a DL360 G4p and a DL380 G3, both of them got fans running, when powered off.

BR

/jag

[RSextonFL · Accepted solution]

gregersenj,

Thank you!!!  Honestly, I am surprised by this, but I also admit that this is my first G4 server I've had my personal hands on.  I've been exposed to many others, but not in a quite enough room to know there was fans running while powered off.  Well, until now.  That said, I am surprised by your answer, but also VERY MUCH RELIEVED!

  thank you for taking the time to confirm this on your end!

Robert

[gregersenj]

You're most welcome :)

There's a power consumption, even when the server is powered off.

ILo is running, as soon as the powercords are connected.

some other subcomponents may use power also. And the powersupplies have a power consumption.

Hence the PSU's must be cooled.

On the DL360 I chekked, fans are in front of the powersupplies, not inside the PSU's.

BR

/jag