BOOSTA on cMP5.1 runs crazy

[pitchbend69]

Hallo,
i have a classicMacPro 5.1 (original) and the BoostA fan runs with 5524 rpm. I cant determine whats the problem:

CPU A Diode 33°
CPU A HeatSink 32 °
CPU A core from PCECI 40°

I changed the cpu and changed the heatsink...but the problem still exists. I also tried to decrease the rpm with MacFanControl...but the fan does not react. What else can i do? Any suggestions?

Thanks for your help!

 

[Alex Sanders74]

Perhaps the temp sensor on that CPU isn't connected correctly or is loose? Do those temps change as you run the machine for a bit or do they fluctuate?

Did you reset the PRAM on boot?

Any led's lit on the board?

 

[h9826790]

What you see in this page?

 

[pitchbend69]

@Alex Sanders74
PRAM reset has no effect, no led is lit, temperature is stable.

i have two cMP5.1. As I wrote, I changed the CPUs and the heatsink from the one to the other Mac...but no effect! When I put the processorboard in the other Mac...the problem still exists. Where can i find the temp-sensor?

@h9826790: This is what I see:

 

[Alex Sanders74]

Seems I was wrong. Temp sensors were on the 3,1 MacPros... no mention of them on the 5,1. Looks like everything is showing properly in your screen grab. System and processor firmwares match which would be my first warning sign if they didn't. Likely why h9826790 asked for the screenshot.

Maybe try reseating the processor tray, SMC reset and PRAM reset?

 

[Slash-2CPU]

Switched CPU and switched fan+heatsink? Software can’t control it? So we know it’s not the fan or the CPU.

SMC reset is simple. Here: https://support.apple.com/en-us/HT201295

The PWM signal isn’t getting to the fan. Either PWM controller on the CPU tray is bad or maybe broken pin on the black socket the fan plugs into.

My two ideas for a fix:

1. (Most obvious) Replace CPU tray.

2. If you’re handy with a soldering iron, run both CPU boost fans from the CPU B boost connector. Not ideal, but will work.

 

[t8er8]

@h9826790: This is what I see:

View attachment 812882

@Alex Sanders74
PRAM reset has no effect, no led is lit, temperature is stable.

i have two cMP5.1. As I wrote, I changed the CPUs and the heatsink from the one to the other Mac...but no effect! When I put the processorboard in the other Mac...the problem still exists. Where can i find the temp-sensor?

Hey bud you should hide that serial number in the screencap as @h9826790 has done, just a heads up.

 

[h9826790]

Since you said even MacsFanControl can't lower the fan RPM. Then it looks very like SMC failure.

TBH, I never seen this. Because when you change CPU and heatsink, etc. You should (I hope you did) disconnect the cMP's power supply (physically disconnect the power cord), and that will effetely perform a SMC reset.

But if you didn't do that. e.g. You simply pull out the tray when the cMP is powered off (but the power cord still connected). Then the very first thing you should do is SMC reset.

Also, did you ever install any other fan control software?

Did you try to boot to recovery mode etc? The fan also crazy in there? (No need any monitoring software, you can tell by just hearing it)
[doublepost=1545950940][/doublepost]

@h9826790: This is what I see:

View attachment 812882

@Alex Sanders74
PRAM reset has no effect, no led is lit, temperature is stable.

i have two cMP5.1. As I wrote, I changed the CPUs and the heatsink from the one to the other Mac...but no effect! When I put the processorboard in the other Mac...the problem still exists. Where can i find the temp-sensor?

Hey bud you should hide that serial number in the screencap as @h9826790 has done, just a heads up.

Yes, better hide the serial number.

In fact, OP can remove the screen capture now. I just want to check the SMC firmware version. And I got the answer already.

 

[pitchbend69]

Hey bud you should hide that serial number in the screencap as @h9826790 has done, just a heads up.

You are right, thx

 

[vonkas]

I suspect damage to fan. Not sure if this works: swap the heatsinks and see if the problem travels.

Hallo,
i have a classicMacPro 5.1 (original) and the BoostA fan runs with 5524 rpm. I cant determine whats the problem:

CPU A Diode 33°
CPU A HeatSink 32 °
CPU A core from PCECI 40°

I changed the cpu and changed the heatsink...but the problem still exists. I also tried to decrease the rpm with MacFanControl...but the fan does not react. What else can i do? Any suggestions?

Thanks for your help!

 

[pitchbend69]

...this fan drives me crazy.

SMC & PRAM reset have no effect...changed everything with disconnected power supply. Fan is crazy in mojave, windows10 & recovery mode. I turn the mac on and the fan is immediately at full rpm. Like Slash-2CPU wrote i think also its the processor-board
[doublepost=1545953452][/doublepost]

I suspect damage to fan. Not sure if this works: swap the heatsinks and see if the problem travels.

You cant swap the heatsinks from boostA and boostB...they are different. I already installed a new heatsink & cpu...has no effect.

 

[Alex Sanders74]

As Slash2 suggested, try plugging the wild Fan on boost A into the B connector and see if it goes nuts. Would rule out the wiring for that fan at least. Sorry this is plaguing you to the degree it is.

 

[pitchbend69]

As Slash2 suggested, try plugging the wild Fan on boost A into the B connector and see if it goes nuts. Would rule out the wiring for that fan at least. Sorry this is plaguing you to the degree it is.

But...i already changed the whole heatsink+fan from another MacPro without change...i am sure it cant be the fan.

 

[Alex Sanders74]

At a loss here... Maybe a new CPU tray is needed after all. From the sounds of it, the fan was doing this before a CPU swap?

 

[Macschrauber]

You can add a ntc resistor, mount it to the heat sink - into the Voltage line of the fan. Like the old days where fans had temperature sensors in the vcc line. Worth some experimenting before buying a new board.

 

[h9826790]

OP, you mentioned about try MacsFanControl.

Can you provide the screen capture of MacsFanControl as well? Those reading may provide some hints about what's wrong.

 

[pitchbend69]

OP, you mentioned about try MacsFanControl.

Can you provide the screen capture of MacsFanControl as well? Those reading may provide some hints about what's wrong.

Here it is...
[doublepost=1546019970][/doublepost]

At a loss here... Maybe a new CPU tray is needed after all. From the sounds of it, the fan was doing this before a CPU swap?

There was no CPU swap...the problem was from one day to another without any hardware changes of the original cMP. I did the CPU swap only to see if the CPU is the problem.
[doublepost=1546020162][/doublepost]

You can add a ntc resistor, mount it to the heat sink - into the Voltage line of the fan. Like the old days where fans had temperature sensors in the vcc line. Worth some experimenting before buying a new board.

interesting idea...is worth a try

 

[handheldgames]

Thanks for posting the screenshot from macsfancontrol. Nothing is standing out like an issue.
[doublepost=1546030616][/doublepost]Boost A is your pcie bay fan. What do you have in your pcie slots?

There is a known issue where the cMP runs boosta at higher rpms until 3D content is displayed. A MacOS app was developed as a workaround and is available on a thread in this forum.

 

[mattspace]

disconnect the cMP's power supply (physically disconnect the power cord), and that will effetely perform a SMC reset.

curious if that's specific to removing the cable from the socket in the back of the machine, or does it occur when you switch off the wall socket, but leave it plugged in?

 

[h9826790]

curious if that's specific to removing the cable from the socket in the back of the machine, or does it occur when you switch off the wall socket, but leave it plugged in?

I didn’t see any mechanism inside the PSU socket. So, I suspect the real requirement is just “remove the power”.

 

[Macschrauber]

What about a deep nvram reset ? 4 times in a row during cold boot until the boot chime gets loud ?

 

[h9826790]

What about a deep nvram reset ? 4 times in a row during cold boot until the boot chime gets loud ?

Apple support told me that need 4 chimes to get a deep reset. I can't find any reference, but that's what Apple told me.

And the very first chime should be normal, but the 2nd one should already reset the volume, therefore, should be "loud" already. The 3rd and 4th chimes of course will be loud as well.

 

[Macschrauber]

I ll count next time, I do a lot with 2006 and 2008 MPs so theres a difference, maybe.

 

[crjackson2134]

I’ve never found any documents stating that beyond 2 chimes are needed. That said, I find that 3 chimes are almost always necessary for correction to my particular problems. If you want to be confident that you have fully reset, I too suggest 4 chimes.

I have a theory about why the 4 chimes could be beneficial, but I won’t post it here because it may be nonsensical and I’d rather not interject any misinformation.

 

[Macschrauber]

Does someone knows what a

nvram -c

does ?

Simple reset like holding alt opt p r - or a deeper reset ?