MP 1,1-5,1 MAC PRO early 2009: 1333 RAM memory running at 1066 (2Rx4 model)

[Jedispirits]

Hi all,

I need your help.

I know it is a discussed topic but in my case It seems to be a little more complicated.

I have a DUAL CPU Mac Pro (early 2009), updated to 5.1 and 2 x 6Core Xeon X5675.

I decided to update the memory to a faster one and I bought 2 modules: 16GB Samsung DDR3 10600.

I was very surprised when a see that the speed was not 1333 but 1066 !!

Then I searched on the net and I could find the problem: I BOUGHT A 4Rx4 MODEL !!

Ok it was my fault. Then I bought two new modules of this other model:

Samsung
M393B2G70BH0-CH9
16GB 2Rx4 PC3-10600R

It should work but.... again it only works at 1066 !!

Of course before you ask, I did several NVRAM resets, tried diferent positions, disabled SIP......

Anyone can help me?

Thanks a lot,

Llorenç

 

[Snow Tiger]

Hi all,

I need your help.

I know it is a discussed topic but in my case It seems to be a little more complicated.

I have a DUAL CPU Mac Pro (early 2009), updated to 5.1 and 2 x 6Core Xeon X5675.

I decided to update the memory to a faster one and I bought 2 modules: 16GB Samsung DDR3 10600.

I was very surprised when a see that the speed was not 1333 but 1066 !!

Then I searched on the net and I could find the problem: I BOUGHT A 4Rx4 MODEL !!

Ok it was my fault. Then I bought two new modules of this other model:

Samsung
M393B2G70BH0-CH9
16GB 2Rx4 PC3-10600R

It should work but.... again it only works at 1066 !!

Of course before you ask, I did several NVRAM resets, tried diferent positions, disabled SIP......

Anyone can help me?

Thanks a lot,

Llorenç

What OS are you using ?

Are you mixing memory module models ?

 

[Jedispirits]

What OS are you using ?

Are you mixing memory module models ?

HI ST,

I'have installed the most updated Mojave (I'm not on a Catalina without official SUPPORT)

I only used modules of the same type. I tested them one by one and in different positions and it doen't work either.

Thanks a lot for your help

Llorenç

 

[majus]

This link is to a post with a checklist for this issue:

cMP & nMP {MacPro 4,1 & 5,1} Memory Upgrade Compatibility and FAQ

There seems to be a lot of confusion about this. I will try to be clear and thorough so we can put it to rest. Several CPU configurations that Apple shipped in the 4,1 and 5,1 are 1333 capable, so you don't necessarily need an "upgraded" CPU. The CPU upgrade guide identifies which CPUs support...

forums.macrumors.com

 

[Jedispirits]

This link is to a post with a checklist for this issue:

cMP & nMP {MacPro 4,1 & 5,1} Memory Upgrade Compatibility and FAQ

There seems to be a lot of confusion about this. I will try to be clear and thorough so we can put it to rest. Several CPU configurations that Apple shipped in the 4,1 and 5,1 are 1333 capable, so you don't necessarily need an "upgraded" CPU. The CPU upgrade guide identifies which CPUs support...

forums.macrumors.com

Thanks I will post there also. But If anyone has an idea or possible fix, please let me know

 

[Snow Tiger]

Hi all,

I need your help.

I know it is a discussed topic but in my case It seems to be a little more complicated.

I have a DUAL CPU Mac Pro (early 2009), updated to 5.1 and 2 x 6Core Xeon X5675.

I decided to update the memory to a faster one and I bought 2 modules: 16GB Samsung DDR3 10600.

I was very surprised when a see that the speed was not 1333 but 1066 !!

Then I searched on the net and I could find the problem: I BOUGHT A 4Rx4 MODEL !!

Ok it was my fault. Then I bought two new modules of this other model:

Samsung
M393B2G70BH0-CH9
16GB 2Rx4 PC3-10600R

It should work but.... again it only works at 1066 !!

Of course before you ask, I did several NVRAM resets, tried diferent positions, disabled SIP......

Anyone can help me?

Thanks a lot,

Llorenç

Have you tried resetting SMC ?

Unplug your Mac's power cord for 15 seconds . Plug power cord back into Mac and wait 5 seconds before pressing the power button .

Reset the SMC of your Mac - Apple Support

The SMC is responsible for managing power on your Mac. Resetting it can resolve certain uncommon issues related to power or thermal management.

support.apple.com

 

[Jedispirits]

Have you tried resetting SMC ?

Unplug your Mac's power cord for 15 seconds . Plug power cord back into Mac and wait 5 seconds before pressing the power button .

Reset the SMC of your Mac - Apple Support

The SMC is responsible for managing power on your Mac. Resetting it can resolve certain uncommon issues related to power or thermal management.

support.apple.com

Yes I did

 

[Snow Tiger]

Yes I did

Hmmm ... does your Mac have any red LEDs that stay on during an OS session ? Disregard lights that briefly flash on at start up . May have to open side access panel .

 

[MIKX]

Have you done a " THREE CONSECUTIVE CHIMES" NVRAM re-set ?

Shut down

Remove the cMP power cord for 1 minute

Hold the Apple Command key + Option key + P key + R key ( all at the same time ) down until you hear the 3rd. chime ).

Fixes a lot of problems.