MacPro3,1 & PC2-6400F

[afberendsen]

Hi there.
I have a MacPro3,1 with 16GB of PC2-5300F. Yesterday I received my new memory: 32GB PC2-6400F. For my surprise, the Mac stops at the beginning of the start-up, and the front light keeps flashing in regular intervals. What I know so far:

1. Flashing light implies bad memory
2. The new memory modules I have ar all 4GB 4RX8 PC2-6400F-555-11-ZZ (4GB, DDR2, 800, CL5, ECC). Those modules where pulled from a working IBM computer (P/N 43X5284 ; FRU:41Y2845).
3. No combinations of memory module make it work. I followed the patterns from http://manuals.info.apple.com/MANUALS/0/MA430/en_US/MacPro_Early2008_MemoryDIMM_DIY.pdf
4. EveryMac and AppleSerialNumberInfo, both shows that my mac is a MacPro3,1 (Early 2008) "Eight core 2.8GHz", which should support by spec DDR2 800MHz.
5. This is the module details (1st page, 1st row): http://smartmconfig.com/ext/ind/docs/ds/SG5127FB212851UUDL.pdf

Any ideas?

 

[nperei]

I suggesting you to test 2 pair(2x4GB) once a time. see if boot normal. that way you know you it good pair. then go next one.

 

[afberendsen]

That's was first action. Same results. Any more ideas?

 

[Spacedust]

4Rx8 is not supported by Mac Pro, only 2Rx4

 

[afberendsen]

Thank you. This is exactly what I found this morning....

http://www.dataram.com/blog/?p=32

 

[ChaosControl]

4Rx8 is not supported by Mac Pro, only 2Rx4

That's good to know
I suspected that but I was never quite SURE

I always made sure that people ordering from mac titled sales got 2R just to be safe and everything was always fine
Still very good to know
Thank you

PS: Does that apply to 1 comma 1 and 2 comma 1 and 3 comma one?