Mac Pro 3.1 black screen, loud fans

Hello, I have a 2008 mac pro 3,1 also. I bought this used thinking it be a great powerhouse to have but in return I have the same problems as you. I've been running OSX El Capitan and it crashes. I have switched out from 2 SSD's and 1 hard drive. Still crashes. I then ran bootcamp to make it a windows machine. While in the windows partition, it still crashes. I have swapped out the ram also like you have tried but no good has come out. I was wondering if you have had any success in the last 5 days since you have posted.

Hi roger

I am out for holidays now but as far as I tried I did not had any improvement in this situation.

It s a good thing you he tried with windows I was wondering if it could be os dependent... Your experience seems to prove it is not.

SSo obviously it s a hardware matter.

do your macpro crashes exactly the same way? Sudden black screen then 7-8seconds wait then huge fans activity. Led diagnosis indicate power and efi but nothing else?

WWhat is your exact configuration?

IIn my last hypothesis I was wondering about the psu that could suddenly stop working correctly or make a short with something or just power off the CPU parts of the logic board

JJust before I left I tried monitoring the current with a software. I did not noticed anything about voltage or current variation before the crash in gpu CPU or ram or global psu...

I Asked myself if it could be a bad short circuit or like in keyboard or mouse !!!

Hello Paul,

Yup i get a black screen then fans start blowing hard. I also tried out different OS X versions but still had the same problem. I have 18 gigs of ram, duel 2.8ghz quad core, nvidia gt 120. I feel like it must be the ram, or the connection of the ram riser to the whole system. My ram connections can sometime not be read as 18 gigs, when i switch the ram around. Also it gets pretty hot. When I have the case open and boot up the machine, I can see the Dimm led lights light up. Sometimes all the dime lights or one or two. I also have the problem where the machine can run fine for hours. But if i let it go to sleep, then wake it up after a couple hours, it will crash as always. I can disable it from sleeping and it will work. Then random crashes.

Also I have tried two different SSD's and a old fashion hard drive. Still the same problem with all three storages.

The kernel panic report from 6-April indicates that panic was caused by ATAPI devices. The only such devices in your model Mac Pro are the DVD reader(s).

THanks grant

I Realized that last time I opened it I may have I inversed the two connectors but I only use one SuperDrive so ... Does it matter?

TThe kernel report say no os? It could be when I was using the recovery partition?

FFor roger I did not notice ram error very often it occurred only one time earlyer in the forum. As far as I saw each dimm are recognized from 4 to 32go.

SSo I did not ask myself if it could be from the riser ? Could it ?

the ram can get hot but since I installed th fan manager it never get hotter than 60•c usually 50 to 54.

TO garret does it worth trying a new psu? Is there a way to check this one ? Could my doubt about keyboard and mouse be real?

thanks

I may have I inversed the two connectors but I only use one SuperDrive

The cabling ships with cable-select addressing.

Does it matter?

A kernel Panic ends whatever you are trying to do. So yes, a kernel panic matters. ¿is drive position the cause of the kernel panic? I have no idea.

Ok ,now I'm getting confused.

Last week I openened and look inside the power supply, nothing looked wrong.

I did not use it until yesterday.

It crashed four or five time, in the morning each time I restarted it very quickly.

And now It 'has been running for 24 hours without failing... doing some batch import of pictures

... still very strange, it crashes after more than 24 hours working, did about 4-5 crash during the few hours after, and then It worked fine rendering huge dpx timelapse in media encoder for more than 30 hours untill now...

Hi guys

Mac pro 3.1

32 gb

hd7950 Mac edition

OWC 250ssd 6g

connected 2 screens (24"monitor and 48" tv")

I use this computer for the general purpose only , googling n watch movie online.

It was fine before I updated 10.11.5 "it was running 10.11.3 , I didn't update 10.11.4" .

the screen black out n after few seconds fan making noisy . This happens when I m watching movie "online streaming full screen in 48" tv" within 20mins in most case.

if the computer in sleeping mode, sometimes black out in the mid night, becuase I woke up by the fan noisy, Sometimes ok for 24hrs.

I have noticed by leaving the case open, it last longer before the screen black out when I watching moive. I have tried everything that I knew expected swapping the old gpu, so far nothing is working

im restoring it back to 10.11.3 from time machine, it is going to take 1 hr from now.

if it happen again, I will hv to try the old gpu for trouble shooting. hopefully not!

I hv a feeling it is got sth to do with the latest EL 10.11.5 version

The RAM in the 2006-2008 Mac Pros run hot and fail with time and that could likely be the cause of your problem.

Periodically look at the memory tab in About this mac and see if all memory is showing and is showing OK. The Mac pro came with ECC memory which corrects most memory errors but when they become too many it can't correct them.

HI lllass,

all rams show up in abt this Mac. if after restored got same issues, I will put the orginal 2 gb ram back for testing.

thank you for advise 🙂

El capitan 10.11.3 looks gd! No black out in last 40mins.

runing 3 x youtube clips in safari and 1x HD clip in VCL

after Memory Clean updated new version, the black out issues comes back."2nd times" I restored it back to 10.11.3 and deleted the apps immidiatly.

and keep observing for tonight.

i have noticed the diffirence, as soon as the black out happened, it comes back frequencetly.

after a restore, it seems fine for at least few hours.

I still suspect a RAM problem. The correlation with Mem Clan helps point to that. After you run it for a while the Mac would use different memory locations so that it could those that are bad.