MP 1,1-5,1 2008 Mac Pro crashing/Fan issue

[Gothboy1]

I thought it was an HD issue. It would boot up, then 5 minutes later the fan would start getting loud like it was working really hard and in the midst of that would crash leaving the on/off light flashing until I turned the Mac off. I removed the boot HD thinking it was mechanical failure and booted off the cloned backup drive but it did the same thing so I’m a little perplexed as to what’s going on. Any help would be greatly appreciated

2008 Mac Pro running 10.11.6
4 HDs Intel 16 GB RAM

 

[840quadra]

Moved to the Mac Pro Forum as you will likely get more visibility / support in that area.

Some questions

1. Have you looked into the Console Application and taken a peek at logs?
2. What section (or zone) are the fans going hyper fast?
   1. CPU Zone ?
   2. Expansion cards zone?
   3. Power supply area?
3. Are there any warning lights on either of your memory expansion bays?
4. Have you replaced CPUs or heat sinks since purchasing your 3,1?

 

[Bigwaff]

Replace the PRAM battery on mobo.

 

[bmoraski]

Are you running any temperature apps ? Such as macfans etc. May need new thermal paste.

 

[Macschrauber]

Replace the PRAM battery on mobo.

There is none. The battery is for the real time clock.

Tho a worn out rtc battery can cause issues, as well.

Back to topic: check temperatures,
check heatsinks,
Test the box with one riser at a time, if nailed to one, swap Ram sticks.

 

[840quadra]

Safe to assume issue is resolved?

 

[Gothboy1]

No not resolved. What I have discovered after a lot of testing is that the fans only run hard when Google chrome is up and running with outlook email loaded. Google version V103.0.5060.134 is the last update that works with my aged OS 10.11.06 MP and is what I’m currently using. I thought I’d use DuckDuckGo instead but its system requirements 12.3 aren’t compatible with computer either. So now looking for browser compatible with El Kapitain if such even exists

 

[840quadra]

No not resolved. What I have discovered after a lot of testing is that the fans only run hard when Google chrome is up and running with outlook email loaded. Google version V103.0.5060.134 is the last update that works with my aged OS 10.11.06 MP and is what I’m currently using. I thought I’d use DuckDuckGo instead but its system requirements 12.3 aren’t compatible with computer either. So now looking for browser compatible with El Kapitain if such even exists

For my late 2008 MacBook Pro, I run Arctic Fox with no issues in El Cap. It is a currently supported open source project that has quite a few users here on MacRumors that also enjoy using it.

Arctic Fox

There are other options as discussed in the Early Intel Mac thread.

Early Intel Browser Thread

 

[OldMacs4Me]

FWIW I had a similar issue, except there was no fan noise. Problem was a dead fan on the graphics card, which would over heat and crash the computer. I was able to do a temp fix with a 5 inch box fan I set inside, leaving the side cover off. That kept it going until I could get a new (to me) graphics card.

Have you cleared any dust out, particularly from the fan on the graphics card but also the main fan?

This is a FWIW but in order to use a more up to date browser, I was using my MP 4,1 in target mode while I prepared and tested Sierra (10.12.6) before installing it on my 2011MBP. Once I had the test version up I discovered the MacPro would also boot from Sierra with no issues, even though it is still the original firmware. Not at all sure you would be able to do a direct install. I would limit myself to installing it on a fresh drive rather than installing over your version of ElCap. Obviously you need to get the overheating under control first.

 

[CompoteComplot]

I would download some app for temperature monitoring (such as Macs Fan Control) and check all the temperatures. Chances are, that your ram is overheating (those 800 MHz DDR2 FB-DIMMS tend to get a bit toasty) or perhaps the Xeon CPUs need a repaste (For all we know, they could still be running on the dried up remains of whatever paste they put there in the factory). Another possible culprit could be the graphics card (What sort did your Mac Pro come with? Is the fan spinning?). Lastly, it might just be one of the temperature sensors going haywire. You can check for that by running the Apple Hardware Test.