Red light showing from processor/memory board

[timd123]

Hi - I have a similar problem so am researching the solution. I'm pretty sure its a temperature/overheating issue.

Has anyone performed an Apple Hardware/Diagnostics Test to see if the computer can tell you exactly whats wrong with it. ( I'm actually having trouble running the test which is a question for another forum!!)

I've added a pic with my temperatures, are these normal or abnormal!?

Thanks

 

[Dlprod3]

I searched this but found different people say different things. I recently had my logic board replaced by a mac technician and now a red LED light is always on next to the processor. Even when the Mac is turned off.
View attachment 465728
The memory seems to be alright showing all 24 GB in About This Mac and the mac runs properly it's just this red light wasn't on before the logic board was replaced.

Hi

Did you wind up resolving this? I have almost the same problem except, my red light is off when the Mac is turned off. Mine powers up but doesn't boot at all with no signal to a monitor.

 

[EvilMonk]

Check your Northbridge Spring Retainer Rivets on the processor tray .. and yes. . de-dust the heatsinks.

This fixed the issue on my 2010 12 cores x5690 ?

 

[Dlprod3]

This fixed the issue on my 2010 12 cores x5690 ?

Thank you. I will try it.

 

[Dlprod3]

This unfortunately did not fix the issue. Any other suggestions? Has anybody finally diagnosed and found a solution to this issue???

 

[iChan]

Hey all! Pretty new here and did my best to exhaust all the forums but I can't seem to get to the bottom of it.

My issue is very similar to you guys -

Running macOS Mojave 10.14.6 on a 4,1 flashed to 5,1 cMP
2 x 3.46ghz 6-core Intel Xeon
32GB 1333 MHz DDR3
RX580 GPU


So my issue is, I was originally running 10.14.4 via DosDude's hacked method - running a slow 5870 powering 2 monitors and 2 x 2.26ghz.

I went ahead and followed @tsialex walkthrough for installing mojave via mac updates, doing a clean install of High-Sierra to clear the hacked install of Mojave. All seemed well, GPU and New CPU's running well but then ran into a red light on the CPU board and only showing 28GB instead of 32GB. Can't really place the cause since it's my first time dealing with it.

I reseated all the RAM, reseated the CPU's and the light went away, showed all 32GB of RAM - but then, about 10minutes in, the computer froze and restarted, and red light is back on along with only showing 28GB of RAM.

Issues that accompanied it is the CPU load, for something as simple as exporting 20 images to desktop from Lightroom, is 98%! That's new. RAM pressure is sky high as well - did a PRAM reset and it worked out, so don't have any screenshots of that - but hopefully someone can provide a bit of insight.

Provided a screenshot of where the light is showing up. It looks to line up with dsd706 but no idea that is either, so I could be wrong on that correlation.

Thanks in Advance!

I'm using my cMP 4,1>5,1 as an unRAID server and I encountered exactly the same issue. Everything was running fine until that light suddenly showed up.

I rebooted the box and got this...

I removed the RAM in Slots 1+5 and the light went away but the error still appears upon restart.

It looks as thought all the processor cores/threads are working fine however.

I haven't removed/cleaned the cpus and heatsinks yet.

 

[RolfNoot]

I had the same red LED lighting up. Turned out be be a defect RAM stick in slot #1, swapped it and now it's all okay.

 

[haralds]

I had the CPU #2 light up after a processor replacement. This is after a long story:

• I decided to upgrade from 3.0GHz Dual Xeons to 3.46Ghz. -> Don't - it's really not worth it. But for 60 bucks, I could not resist.
• I have a brace on my thumb for an injury and became clumsy. I dropped the chip while trying to insert CPU #1. Two socket pins bent, CPU tray GONE. $125 later, I am at try number two.
• This time, I am super careful, but I after partial assembly, I try to test the setup without paste or tightening down the heat sinks. I was not sure whether those cheap CPUs were ok. Those Xeons cannot get that hot in 20 seconds, right?
• Get the dreaded red failure LED.
• Try the known working chips. Same thing!
• Now I am sweating!!!
• I decided to do one last test and go all the way. I applied my tube of Kryonaut paste with the 3.46Ghz chips, tightened down the heat sinks, and put in all six RAM sticks.
• And it ... just worked!

The lesson here is that the thermal system will cause failure very quickly, if not set up right or not working properly.

 

[Macschrauber]

I only test CPUs without heat sink until the machine bongs (and so tell post ok) and do suddenly kill power. Without drives of course.

 

[haralds]

I only test CPUs without heat sink if the machine bongs and do suddenly kill power. Without drives of course.

The Mac Pro posted fine but alarmed a few seconds into booting and then shut down. Will it post with one of the two CPUs faulty?

 

[Macschrauber]

don't post with one faulty CPU, but you can left the 2nd cpu empty.

Don't go further than post without a heat sink. I'd also do not recommend doing this. I have a half defective cpu board what I use for this tests.

The voltage regulators are without cooling, also. It's a very rude method. I just do that before delidding.