MP 1,1-5,1 MacPro 5,1 upgrade RAM

[Zail Si]

Hi there,

I have a 5,1, 2 x 2,66 Mhz running Mojave and decided to upgrade the current 4x4GB for 8x8GB Samsung, but on slot 2 I get the red board light and that dimm isn't recognized.

When I put back the old ram like it used to be everything is fine, no red light and the dimm is recognized like always.

I have tried every single combination of dimms, swapping them, installing them one by one and reseting NVRAM to no luck,.. each time there's a dimm on slot 2 I get the board slot red light, however when I put back the old dimms it works fine.

The new dimms are from another 5,1 and they are all OK.

What is going on?

 

[tsialex]

Hi there,

I have a flashed 5,1, 2 x 2,66 Mhz (delided) running Mojave and decided to upgrade the current 4x4GB (Kingston KVR 1066 D3N7/4G) for 8x16GB Samsung 2Rx4 PC3L dimms, but on slot 5 I get the red board light and that dimm isn't recognized.

When I put back the old ram in slots 1-2 and 5-6 like it used to be (or just 2 in slots 1-5) everything is fine, no red light and the dimm is recognized like always.

I have tried every single combination of dimms, swapping them, installing them one by one and reseting NVRAM to no luck,.. each time there's a 16Gb dimm on slot 5 I get the board slot red light, however when I put back the old dimms it works fine.

The new dimms are from another 4,1 (5,1) and they are all OK.

What is going on??? it's driving me crazy!

Probably a bad pin connection on the Xeon socket somewhere.

Remove the processor that is linked to the bank that have the red light, check the socket pins and the contacts on the PCB of the Xeon processor.

Some non-oil contact cleaner spray will help too.

 

[Zail Si]

Probably a bad pin connection on the Xeon socket somewhere.

Remove the processor that is linked to the bank that have the red light, check the socket pins and the contacts on the PCB of the Xeon processor.

Some non-oil contact cleaner spray will help too.

Thank you for the reply tsialex, I will have a look at those things