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MP 5,1 upgraded to pair X5690, fans running high

M

Mister Speaker

macrumors member
Original poster
Oct 14, 2016
32
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Hi there. I have a refurbished Mac Pro 5,1 (mid-2010). I just recently grabbed a pair of Xeon X5690 SLBVX 3.46GHz chips and had a friend install them. Since the install, my fans have been running full-tilt - resetting the SMC and PRAM has no effect, and I took off the heatsinks to make sure nothing had disconnected or obstructed their thermal sensors. The machine also does not chime when it starts up.

I took the machine in for a diagnostic and just received it back; the tech said that "the machine is not receiving thermal information from the CPUs" but would not elaborate when I asked WHY, or if there is any other solution than "put the old chips back in." As with any of this stuff you hear a lot of different theories from different people so at this point I'm pretty confused... Now I'm hearing that there may be compatibility issues deeper than "make sure you get the X5690 SLBVX model" - I'm going to peruse the CPU compatibility thread in this forum and try to shed some light on that. Would sharing the machine's serial # help gain insight on potential compatibility problems?

I'm just really hoping there is not some deeper compatibility issue, and that this is something I can solve without having to buy another set of CPUs. Any insight would be hugely appreciated, thanks for your time.
 
Enough people have installed the x5690 that I doubt there is a compatibility issue, unless you have an Engineering Sample or bad CPU.

The system monitors CPU temperature and runs the fans up or down as needed in order to keep the CPUs in a safe operating range and also to run the fans as quietly as possible. Fans go full-tilt for two main reasons:
  • When the CPU is really hot, the fans go full tilt to try to cool it down.
  • When the system does not get CPU temperature information at all, the fans go full tilt because it doesn't know what a safe fan speed is without knowing what the temperature is.
For the first situation it probably means incorrect installation of the thermal paste or heatsink, causing the CPU to get really hot. This would be easily fixed by reinstalling it correctly.

According to the tech, if we take him as correct, the second situation is occurring and your system is not getting temperature information at all. I don't know how to fix this since I don't know where the sensor is or how it is connected.

You can verify which situation is occurring by installing temperature monitoring software yourself and seeing if the CPU temperature is really high or is not being reported at all. I like "Mac Fans Control" but there are many others like iStat.
 
Are you sure the heat paste is well applied and that the CPU heat sinks are properly installed?

As said above, The CPUs have temp sensors in the core and will instruct the fans what speed to run. You should get some software that lets you see the reported temp of the CPUs.

The 2010 model can have the CPUs installed with lids on them if I recall correctly, so do they have the lids on them? If not there would be a dangerously large gap.
 
prvt.donut said:
Are you sure the heat paste is well applied and that the CPU heat sinks are properly installed?
Click to expand...

Yes, the installation was done properly by someone I trust. He did not de-lid the CPUs.

I'll try a third-party temperature readout but I worry it's just going to tell me what I already know: that the temperature isn't being communicated from the chips. I want to know WHY it's not, so I can fix it properly.
 
Are you using the same CPU tray as originally came in your Mac?

On the hardware overview in System Profiler, do the SMC versions for the system and processor tray match?
 
scott.n said:
Are you using the same CPU tray as originally came in your Mac?

On the hardware overview in System Profiler, do the SMC versions for the system and processor tray match?
Click to expand...

Under 'hardware overview' I'm only seeing one SMC Version, '(system)', 1.39f11

Should I be looking somewhere else for the other SMC Version, or does the lack of it mean it isnt the original CPU tray?

EDIT: I found a file called SysLog.txt which was last updated in April (right around the time I bought the machine). It shows matching serial numbers for system and processor tray SMC Versions - 1.39f11.
 
You should see something like this on the main start page of System Information:

SMC Version (system): 1.39f11
SMC Version (processor tray): 1.39f11

Are you only seeing the one entry for the system?
 
If you look at the fan speeds in iStat or a similar program, are either of the boost fans at 0rpm? I upgraded mine and had the same problem as you when I booted up and it was one of the heat sink plugs was loose, I was able to tell which one as Boost A was showing 0rpm whilst Boost B was running as it should. Pushing the plug in a bit more connected it properly and now my fans are fine.
 
The general methodology when installing processors in a dual processor cMP is to install one, boot the machine and insure it is properly installed with thermal sensor reattached. Then install the second. This allows you to determine if you haven't seated your sensor, chip, thermal compound or heat sink properly for each processor.

If your friend didn't test as he went there's no way to know which processor is awry. The fan issue is a common problem if the heat sink isn't attached properly or if it isn't ratcheted down to the correct position.

I would have the processors reinstalled properly. Almost certain to resolve the issue. This forum is absolutely chalk full of the information you're looking for. I have always recommended pindelski's guide for processor upgrades on cMP. I and countless others have used it successfully. You can find links for it here on the forum, though I believe they all point towards archives at this point as the original website is no longer in operation.
 
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if one of the cpu is not working properly, the firmware assumes its overheated and maxes fans. i just had this happen on my 2009 cpu upgrade. the cpu was not tightened down square. @thornslack laid it out. i did one cpu first, so i knew the second one was not working.

ps--up and running now! thanks macrumours!
 
So this is weird. I just fired up the machine and got no fan noise. Checked the System Profiler and both SMC Versions are showing up and identical. To make sure things were actually working, I downloaded SMC Fan Control and all temperatures and RPMs are within nominal levels.

Problem solved, I guess? Many thanks to everyone for all your help.
 
I spoke too soon. The fans are going full-tilt again, and all I did was connect my peripherals and move the tower back under my desk. :(
 
h9826790 said:
So, what you see in SMC Fan Control now?
Click to expand...

Right, forgot to mention that as I was posting from my phone. Something is definitely out of whack with the fans, both BOOSTA and BOOSTB show 000RPM and the temperature showing is 128C. For the record, the computer is currently NOT on fire.
 
I suspect loose heat sinks on the processors and or loose thermal sensor. The sensor is attached to the heat sink so could be a combination of the two. As per my earlier advice I think you need to remove and reinstall the processors, making extra sure this time as the thermal compound is applied, the thermal sensor is re-attached and the heat sink is placed back on and tightened down.
 
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I have taken the CPUs out and put them back in about half a dozen times now. I've tried the old chips to no avail. Currently still showing 128C and 000rpm; BOOSTA/BOOSTB 0rpm in SMC Fan Control, and now both INTAKE and EXHAUST are over 2000rpm.

I did, however, find what I think is the culprit: The fan/sensor connector in the rear CPU heatsink is a little loose. Where the connector on the other heatsink is firm and does not move at all, this one wiggles a bit. It doesn't appear to be broken, all the tabs are in place. It also seems to be connecting to its counterpart on the tray just fine. A friend said it could be a wire inside the connector that's broken - is there any way to test this with a voltmeter? I'd really rather not have to shell out another $500 for a heatsink...
 
Last edited:
Something doesn't sounds right, if only one heatsink's connector loose (e.g. Heatsink A), then Boost B fan speed should be still avail.

Also, which temperature shows 128? CPU or Heatsink?
 
SMC Fan Control shows ~128C and 000rpm on the taskbar readout. Clicking on it to reveal individual fan temps shows BOOSTA/BOOSTB at 0 rpm.

This is getting even weirder: The fans are now intermittently turning on and off. They'll run full blast and then turn off for a few seconds at a time. What does this mean?
 
Did you have fan problems when you put the old CPUs back in?

Are any of the pins in the sockets damaged?
 
Yes, as I said before, installing the old chips made no difference.

No, there don't appear to be any bent or damaged pins in the sockets.
 
I think these are the part numbers (different parts for CPU A and B), but verify before buying.
076-1367
076-1368
 
Because one of the heatsink connectors felt loose, I tried a fix described at about 4:15 in this video:


I gently removed the connector and clipped off the tabs holding it in place. Then I unstuck the wires from the heatsink and pulled a little extra slack out for the connector, which I ensured was connected manually before reattaching the heatsink.

It didn't work; the fans are still blowing high. I'm going to try it again and file down the flash remaining from the tabs on the connector, as I can kind of still feel it contacting while putting the heatsink back on.

Barring this, I'm out of ideas. Are there replacement heatsink fan/sensor assemblies out there, or should I get an entirelt new pair of sinks?
 
pastrychef said:
The video is for MacPro4,1. On dual CPU 5,1s, the connector shouldn't be an issue. It fits back in once the heatsinks are tightened.
Click to expand...

As I said, one of them felt loose in the heatsink and I think ir might not be making a positive connection to the board.

If both BOOSTA/B are showing 000rpm and the temperature reads 128C, it must be something not communicating between the sensors and fans in the heatsinks, right? Is there any other sensor on the CPU board that I could have missed?
 
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