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joehack
Jul 8, 2006, 06:23 AM
To my knowledge, the MacBook supports dual channel memory access if 2 identical modules are installed. I've installed 2 corsair 1GB modules (makes 2gb ram) and I assumed this enables dual channel memory access.

Today I've looked into Apples System Profiler and it showed me 2 entries:

DIMM0/BANK 0:

Size: 1 GB
Type: DDR2 SDRAM
Speed: 667 MHz
Status: OK

DIMM1/BANK 1:

Size: 1 GB
Type: DDR2 SDRAM
Speed: 667 MHz
Status: OK


It seems like it does NOT run in dual channel mode. Or am I wrong? :confused: :confused:

Regards,
Jochen


generik
Jul 8, 2006, 06:44 AM
I think it is not shown in system profiler :)

Most likely it is handled somewhere really low level like during bootup in BIOS and is totally transparent to application software.
joehack
Jul 8, 2006, 06:55 AM
Whats puzzling for me is the fact, that it shows BANK 0 and BANK 1. With a dual channel configuration, I've expected only a BANK 0.
dmw007
Jul 8, 2006, 07:06 AM
I think it is not shown in system profiler :)

Most likely it is handled somewhere really low level like during bootup in BIOS and is totally transparent to application software.


I think that you are right generik- none of the RAM in my Power Mac G5 lists as being 'dual-channel' but allow of the RAM modules are most certainly matched pairs. :)
joehack
Jul 8, 2006, 07:13 AM
@dmw007: how many memory modules do you have installed? can you send a screenshot from the System Profiler's memory section?

Thanks!

Joche
generik
Jul 8, 2006, 09:23 AM
Whats puzzling for me is the fact, that it shows BANK 0 and BANK 1. With a dual channel configuration, I've expected only a BANK 0.

Erm... I am not really sure what you expect system profiler to show for this, but I can assure you that you are wrong with regards to what bank means. Each bank indicated in system profiler actually refers to a physical DIMM slot and it has nothing to do with dual channel or not. Dual channel is more with the signalling timings of the memory modules and they are still.. 2 logical modules
FleurDuMal
Jul 12, 2006, 05:43 PM
Mine shows exactly the same (Bank 1/Bank 0) and I installed paired RAM today. I don't think that Bank actually indicates whether its in dual configuration. Though I'm not sure about that.