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FLappleGuy

macrumors newbie
Original poster
Sep 28, 2016
17
8
Orlando, FL
Hey Guys!

Complete newbie here who has learned quite a bit in these forums, which has led me to successfully upgrade my 2006 Mac Pro to Yosemite! I'm very thankful for all the help on here.

When I got the new OS installed, I wanted to check temps and fan statuses to make sure everything was running fine, and I noticed Riser A RAM is running VERY hot. I did some searches here on the forums, and on google, but the highest I ever saw someone report it running was maybe 200F. Mine is coming back at 262F.

The weird thing is Riser B is fluctuating between 130-160F, where as Riser A has been a steady 262F whether I just turned the machine on, or turn the fan speed up, or anything. I can't get it to go down at all, and there is really no software running on it that would be hogging things.

I'm using iStatMenus for the temperature information. The Mac is a 2006 Mac Pro, Flashed to 2,1, running OS X Yosemite with 32GB of RAM. The ram has the flat heat sink, if that contributes to this at all.

Any suggestions you could provide would be much appreciated.

Thanks!

efqlNWP.jpg

QRHwSac.jpg
 

pastrychef

macrumors 601
Sep 15, 2006
4,753
1,450
New York City, NY
Holy moly!!! Those are insane temps. Are you sure the reading is correct??

Maybe you can try using SMC Fan Control to manually crank up the fan. I would not leave the computer on for long with those temps.
 

FLappleGuy

macrumors newbie
Original poster
Sep 28, 2016
17
8
Orlando, FL
Holy moly!!! Those are insane temps. Are you sure the reading is correct??

Maybe you can try using SMC Fan Control to manually crank up the fan. I would not leave the computer on for long with those temps.

So I just took a laser thermometer to the RAM bay area and couldn't find anywhere reading over 130F. Which leads me to believe it's a sensor issue, would replacing the riser card be a wise solution?
 

h9826790

macrumors P6
Apr 3, 2014
16,618
8,552
Hong Kong
Hey Guys!

Complete newbie here who has learned quite a bit in these forums, which has led me to successfully upgrade my 2006 Mac Pro to Yosemite! I'm very thankful for all the help on here.

When I got the new OS installed, I wanted to check temps and fan statuses to make sure everything was running fine, and I noticed Riser A RAM is running VERY hot. I did some searches here on the forums, and on google, but the highest I ever saw someone report it running was maybe 200F. Mine is coming back at 262F.

The weird thing is Riser B is fluctuating between 130-160F, where as Riser A has been a steady 262F whether I just turned the machine on, or turn the fan speed up, or anything. I can't get it to go down at all, and there is really no software running on it that would be hogging things.

I'm using iStatMenus for the temperature information. The Mac is a 2006 Mac Pro, Flashed to 2,1, running OS X Yosemite with 32GB of RAM. The ram has the flat heat sink, if that contributes to this at all.

Any suggestions you could provide would be much appreciated.

Thanks!

efqlNWP.jpg

QRHwSac.jpg

Pretty sure that's the sensors error / software issue, but not real temperature.

262F is the max can be displayed. Which is coming from 128C. And that's coming from 256/2 (half of a byte).

When iStat unable to acquire a valid value, it may display the preset max. e.g. After install FakeSMC, some GPU will shows steady 85C in iStat.

So, I am quite sure that's just the wrong reading, but not a real RAM overheat.

You may swap the RAM between riser A and B. So that you will know if it's the RAM's problem or something else.

Since you said that you are new to the machine, and just finish the upgrade. If the RAM in riser A is different then the RAM in riser B, may be those "hot" RAM simply not have a temperature sensor that compatible to the cMP.
 

LightBulbFun

macrumors 68030
Nov 17, 2013
2,810
3,125
London UK
I can confirm that when the SMC cant read the temp of something (in this case RAM slots with no RAM in them) it will just report the Max temp which is 129c if you look at a Dual GPU MBP when its running with just the iGPU activated the dGPU will report 129c as well (I have 4x4GB sticks with non Mac Pro heatsinks running just fine)

upload_2016-9-28_15-43-56.png
 

Morpheo

macrumors 65816
Feb 26, 2014
1,273
1,589
Paris/Montreal
Riser A is always hot on these Mac Pros. Mine is almost always around 175º under normal use. When the fans kick in of course it goes down a few degrees. But I agree 262º is not correct. Maybe a sensor issue?
 

FLappleGuy

macrumors newbie
Original poster
Sep 28, 2016
17
8
Orlando, FL
After some troubleshooting and trying different RAM configurations, nothing seemed to fix it. Then when I re-arranged the cards back how they were in the first place, temps started displaying as normal!

h9826790 it appears that it was, as you mentioned, just reading the max temp possible since it apparently wasn't receiving a temp from the sensor.

All is well I guess, thanks for everyones help!
 
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