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Chrisf1977

macrumors newbie
Original poster
Oct 16, 2018
18
1
Hello,

while cleaning my MacPro 4.1(5.1) I have probably destroyed a memory module (or memory slot) in slot 1.
After cleaning and startup the Mac a red LED glow near at the memory slot 1. MacOs tells me in Slot 1 is no Memory Module installed. The I have removed the memory module from memory slot 1 and startup the Mac again. The red LED is now off. The I have installed the memory module from slot 1 into the slot two. Now, after the startup, the red LED on slot 2 glow. Then I have installed additionally the memory module from slot 2 into slot 1 and after startup the LEDs from slot 1 and from slot 2 glows. :confused:

Okay, for me is this a sign that the memory module from slot 1 is destroyed so I have buyed two new memory modules. But, if I install this two modules into slot 1 and slot 2 the white power LED on the front of my Machine flashes if I power on the machine. The same if only one new memory module ist installed (in slot 2, slot 1 empty).
Have i buyed the wrong memory modules?:rolleyes:

Old memory modules (4 pieces installed in my Mac):
91mwnBHkTvi0QIzZnr1zpg.jpg

New memory modules (2 pieces for slot 1 and 2):
LIH6QG3gSc6c+%gcwyT3HQ.jpg

My Mac:
Bildschirmfoto 2020-03-12 um 17.48.59.png

Thanks for answers!
Chris
 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
Can i use 4xRDIMM or 4xUDIMM?
Yes, you can.

Please note that the best memory performance possible will be 3x16GB RDIMMs, Nehalem and Westmere Xeons are tri-channel and using 4 DIMMs have some penalties with memory access.

If you have an application that works best with more memory than faster memory, use all 4 DIMM slots, while if you have an application that works best with faster memory than more memory, use just 3 DIMM slots.
 

Chrisf1977

macrumors newbie
Original poster
Oct 16, 2018
18
1
Okay, thank you! Then i will change the buyed memory modules and buy 3x16gb RDimm ?
 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
Okay, thank you! Then i will change the buyed memory modules and buy 3x16gb RDimm ?
Dual rank only. Read the memory thread and see the models that are known to work.

 
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Chrisf1977

macrumors newbie
Original poster
Oct 16, 2018
18
1
3F578C96-F10A-47BA-96B4-7AE03C4FDE33.png
3F578C96-F10A-47BA-96B4-7AE03C4FDE33.png

Sorry last Question: Is this the right module type you can see on the screenshot?
 

Snow Tiger

macrumors 6502a
Dec 18, 2019
854
634
get three of these and you'll be happy :

16GB = Samsung M393B2G70BH0-YH9 (low voltage) .

For a total of 48GB at 1333 MHz .

Remove all other ram from your System first .
 
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Chrisf1977

macrumors newbie
Original poster
Oct 16, 2018
18
1
Good Morning,

thank you all for your help. Now i have buyed and installed three of the Samsung M393B2G70BH0-YH9 Modules. For the the Modules i have payed 75€ incl. transport on ebay :)
 

Jill Valentine

macrumors newbie
Nov 6, 2021
26
1
Sweden
Hello. I have a question about RDIMM in Mac Pro 5.1. A while ago i changed my dual XEON E5620 to dual X5650. I had Hynix 4GB 10600E UDIMM RAM, total 24GB. The X5650 and possibility to run the RAM in 1333 made my Pro much faster.

Afterwards i needed more RAM for Video editing so i switched to RDIMM instead of UDIMM. I bought six 16GB modules and two 8GB, total 112GB. I have High Sierra on one SSD, Mojave on another and Monterey on NvMe.

I put in 64GB first in correct memory banks, booted OK and when i click the 🍏 and see about my Mac it stands 1 warning to the right. In system preferences everything seems OK and the RAM is correct in place. I ran the memoryslot and memory manager utils but i couldnt see anything that was wrong, not sure where the logs are stored, would be a help if anyone know where to find?

The Mac runs fine no problems and are extremely much faster than before. One day I believe it were in “about my Mac” for just a second a notification popped up saying something like “My system are not built for this amount of RAM”
So i was thinking has it to do anything about the both 6-Core X5650 XEON?
Before i changed i had the E5620 which is 8-Core. I dunno.
I have changed places with the DIMM’s, tried different configs, same “1 warning” remains.

For a couple of weeks i have six identical 16GB modules in bank 1,2,3 and 5,6,7
and yesterday i put the two 8GB in bank 4,8.

If anyone could help to explain why that error msg is about, eventually how to fix if there is a problem i would be more than grateful.
 

Macschrauber

macrumors 68030
Dec 27, 2015
2,979
1,487
Germany
Whats written in System Profiler in the Memory section?

Maybe ECC errors. If that occurs try to clean the contacts (dont spray it, just clean them with isopropyl alc.) and reseat them a few times.

Otherwise swap them, if the error dont moves with the swapped one the CPU (contacting) has a problem. If the problem moves with the ram stick the stick has problems.
 
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Jill Valentine

macrumors newbie
Nov 6, 2021
26
1
Sweden
Whats written in System Profiler in the Memory section?

Maybe ECC errors. If that occurs try to clean the contacts (dont spray it, just clean them with isopropyl alc.) and reseat them a few times.

Otherwise swap them, if the error dont moves with the swapped one the CPU (contacting) has a problem. If the problem moves with the ram stick the stick has problems.
Thank you for valuable info. Of what I can see nothing is written there, or maybe I look at the wrong place..? Will clean with isp and see if it helps. Btw dunno if it has something to do with it but when I swapped both XEON i marked up with tape and the T-hex aswell and carefully tighten in correct order. When tightening come to end i read the technical manual i should tight little more, i think a quarter. But in my case that was impossible when bolts came to it’s end there were no way to tighten more, it were like if a bolt/screw came to an end. That was the case of both the XEON so i dunno how ppl can tighten too much? Also i did not see any plastic washers, and the old thermal paste looked like new and not dried. Not sure if the previous owner has changed thermal paste and get rid of the washers, so therefore i could not tighten more?
Anyway i will clean and reseat RAM and see if i can find any info about that warning.
 

Macschrauber

macrumors 68030
Dec 27, 2015
2,979
1,487
Germany
That tighten thing is for lidless Xeon 4,1 dual CPU machines, when someone upgrades it with CPUs with the heatspreaders on.

not to recommend, but as yours is a 5,1 not related.
 
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