Netfinity 4500R power supply failure

[dhollow2]

We have a Netfinity 4500R server that runs for about 3 minutes and then shuts down with a power supply failure fault. We have tried three different power supplies and get the same fault condition with all three. This happens in both bays. If two power supplies are present, both shut down aimultaneously. Both the Light-path indicators and the power supply indicator lights (AC light on, DC light off) indicate a power supply failure, but there is no way all three power supplies are bad. Any suggestions where to look next?

 

[comtec17]

Sounds like you have a bad backplane.

 

[dhollow2]

A couple of things to add to the original post: 1) If I boot to diagnostics, the server will run indefinitely without the power supply fault. 2) The server doesn't run long enough to fully boot to Windows, but I was able to boot to the configuration menu and see the system log before the failure. There are two messages related to the failure: A) Failure Reading I2C device. Check devices on Bus, and B) Power Supply 1 overvoltage fault (There was only a power supply in bay one at the time). My interpretation of this is that overvoltage monitoring doesn't occur in diagnostics mode, but does in configuration and a full Windows boot. I don't think there is an actual overvoltage condition and the overvoltage fault is spurious. Does anyone know what component performs the voltage monitoring? Thanks.

 

[kosekjm]

There are also VRM (Voltage Regulator Modules) for the processors (I think the 4500 has them all of the IBM servers do.)

I'm not sure if they could be the problem, but have you checked to see if the VRM (could be as many as one per cpu) is seated correctly?

Just a thought.

Jim

Although, usaully VRM erros have their own led/diagnostic code, but it might be worth the look.

 

[robdot]

dhollow2,
Did you ever solve your problem with this server?


I'm seeing the same thing.


Thanks,
Rob

 

[jtb33]

I have the same problem with my 4500R as well. Problem is that it will only power on about 1/10 of the time. I just bought a new power supply - same problem.

Did anyone find the solution?

 

[catorze]

Before you spend any more money on parts, take a look at the ASM firmware update for the server. This was fixed via firmware. It's available from:

http://www-3.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-44722

 

[jtb33]

Unfortunately, I can't even get my 4500R to power on now. Grrrr...

The LED near the power button flashes and the Power on indicator on the mainboard (CR56) flashes as well. Both of the power supplies have the green "AC" light on, but it just won't power on. Hmmm...

 

[catorze]

Think BIOS recovery. The procedure is in the HMM. Once complete, flash the BIOS and the ASM firmware.

 

[Dirk186]

Its the VRM. Had the same problem on our 4500r. The diagnostic LEDs on the backplane should tell you if that is so. IBM came and replaced the whole backplane but it was the VRM.

 

[klunde]

I know this thread is old but any, if you're still around Dirk; is the VRM changeable? If it is - where is it?

I have this problem with my 4500r server now and I've managed to check that I'm current on both bios (r11)and Management (1.19).

So far I've tried to change power, change backplane, checking cables...



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[Dirk186]

If I remember right it is. It was next to the diagnostic LED's on the board. When IBM came though, they replaced the whole board. If you need me to try and dig out some documentation, let me know.

JR

 

[klunde]

thanks, I think I found it, but for some very very very strange reason the server has now been running for almost an hour without shuting down - just as I'm running it as cabriolet and just sits here in the middle of the night waiting for it too go down...

BTW, when the diag lights should tell me that it is the VRM should the VRM light on the lightpath light up? on my server I've only seen the PS1 and PS2 lights so far, not the VRM light.

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[Dirk186]

VRM should light up if I remember correctly. If it is totally blown or having an intermittent problem then it might not light at all. If you have tried everything else then that would leave me to believe that the VRM is the issue. Let me know.


JR

 

[klunde]

OK, thanks for your help. I will call IBM first thing in the morning (I'm in Oslo, Norway it's late night here...)


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[klunde]

I just discovered that our server does not have a VRM installed. Is this possible?? Should the server work without the VRM or is the VRM only required if you have two cpu's installed?

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[klunde]

To answer my own question: Yes. It needs the VRM and the slot is empty since there also is an onboard VRM for CPU #1.

My solution to the problem was to buy a VRM for the second CPU slot, install it and move the only CPU from Slot 1 to Slot 2.

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[Dirk186]

I dont understand. Did the server come with 2 cpus and not a VRM?

JR

 

[klunde]

No, the server had only one CPU, but according to an IBM technician you can install the one CPU in either slot but if you want to install it in slot two you must also install the additional VRM. CPU slot 1 has VRM built in on the motherboard.

But now the sad news: My server went down again this weekend so now I think I'm buying a new motherboard as well...

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