32GB RDIMMs that work with MacPro5,1 are 4Rx4 RDIMMs, so, 1066 or 800MHz when installed to a Nehalem/Westmere Xeon.
Since the latency will be lower than at the nominal frequency, the penalty is not so much noticeable in the great scheme of things.
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Crazy idea. 32GB RAM modules in a cMP. Anyone tried this?
- Thread starter William Payne
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32GB RDIMMs that work with MacPro5,1 are 4Rx4 RDIMMs, so, 1066 or 800MHz when installed to a Nehalem/Westmere Xeon.
Since the latency will be lower than at the nominal frequency, the penalty is not so much noticeable in the great scheme of things.
I did this on my MacPro 4.1>5.1 Single Processor, and it didn't work the first time.
In my case, I have an SSD with Windows 11 OCLP (as primary boot) and an NVMe with MacOS Sonoma OCLP (as secondary).
When I made these changes in the NVMe config.plist, the system got stuck on the Apple screen.
In a error attempt, I decided to apply the changes in the SSD config.plist and bingo! It worked perfectly. I have 128GB of RAM (in four 32GB modules).
Since my MacPro only has 4 memory slots, here's what I entered in the config.plist:
Code:
</dict>
<key>Memory</key>
<dict>
<key>DataWidth</key>
<integer>0</integer>
<key>Devices</key>
<array>
<dict>
<key>AssetTag</key>
<string>123456789</string>
<key>BankLocator</key>
<string>BANK 0</string>
<key>DeviceLocator</key>
<string>ChannelA-DIMM0</string>
<key>Manufacturer</key>
<string>Hynix</string>
<key>PartNumber</key>
<string>100-563-491</string>
<key>SerialNumber</key>
<string>80AD01151640E62AB4</string>
<key>Size</key>
<integer>32768</integer>
<key>Speed</key>
<integer>1333</integer>
</dict>
<dict>
<key>AssetTag</key>
<string>123456789</string>
<key>BankLocator</key>
<string>BANK 1</string>
<key>DeviceLocator</key>
<string>ChannelB-DIMM0</string>
<key>Manufacturer</key>
<string>Hynix</string>
<key>PartNumber</key>
<string>100-563-491</string>
<key>SerialNumber</key>
<string>80AD01151640E62AD3</string>
<key>Size</key>
<integer>32768</integer>
<key>Speed</key>
<integer>1333</integer>
</dict>
<dict>
<key>AssetTag</key>
<string>123456789</string>
<key>BankLocator</key>
<string>BANK 2</string>
<key>DeviceLocator</key>
<string>ChannelC-DIMM0</string>
<key>Manufacturer</key>
<string>Hynix</string>
<key>PartNumber</key>
<string>100-563-491</string>
<key>SerialNumber</key>
<string>80AD01150930D7A373</string>
<key>Size</key>
<integer>32768</integer>
<key>Speed</key>
<integer>1333</integer>
</dict>
<dict>
<key>AssetTag</key>
<string>123456789</string>
<key>BankLocator</key>
<string>BANK 3</string>
<key>DeviceLocator</key>
<string>ChannelD-DIMM0</string>
<key>Manufacturer</key>
<string>Hynix</string>
<key>PartNumber</key>
<string>100-563-491</string>
<key>SerialNumber</key>
<string>80AD01150930D7A3A2</string>
<key>Size</key>
<integer>32768</integer>
<key>Speed</key>
<integer>1333</integer>
</dict>My questions are: When I update MacOS or OpenCore to a new version, will I have to redo all this again?
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So this simply means, your machine tried to boot from the (then unedited) OpenCore of your SSD also at the first try.
If you have a GPU showing the native Apple bootpicker by holding Option, you can simply switch between different OC-Versions if you have multiple on your Mac. Each is represented by a Bootvolume named EFI-boot.
Would rather go to three modules. 96 GB are plenty of RAM, but, by populating the fourth slot, you do two bad things:
You loose triple channel, which costs between 10 and 20% of memory performance. And with quad-rank-DIMMs, which the 32 GB modules usually are (shown by "4R" on the label), the real speed drops to 800 MHz, if the 4th socket is populated with an identical module as the other three. The 1333 shown in "About this Mac" are fake / just what you entered in the config.plist.
😎
You can easily check the speed which the RAM is really running using CPU-Z in Windows. Three sticks, running in triple channel, will get you 1066 MHz. And that's all you will get with these 32 GB parts.
If you update OpenCore, yes! The config.plist gets overwritten every time you update OpenCore (i. e. via OCLP). So you have to reenter your edits every time after.
Updates to macOS which do not require an update to OC will leave the config.plist untouched.
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yes absolutely you will. i have the memory mod on my 5,1 also and every update i have to take out the 32gb sticks, re-mod the config list , then put the ram back in. its probably best to set it and not update for a while.
Hmmm, should not be neccessary to re-mod the OC config.plist file for OS updates as long as OpenCore is not updated too.
Also it should not be neccessary to remove any of the RAM sticks. I just re-enter the edits to config.plist after updating OpenCore before i reboot.
you are correct, i must have mis-read something, its all good. if you update OCLP then yes re-mod is needed.
you wont.. i have 128 and it lets my protools run smooth. with 96 i might get an error once in a while. yes it stilll wont use but it works for me.