Mac Pro 3.1 - start up sequence + sounds

[Paul P]

Howdy all,

I recently upgraded to a Mac Pro 3.1 from a Mac Pro 2.1, and I'm curious to know about the start up sequence differences between the two.

On the 2.1, when I pressed the power on button, the chime, drives and fans all started pretty much straight away (and at the same time). On the 3.1, when I press the power on button, the fans(s) whir at high speed for about 5 seconds, then you hear the chime, and then the computer starts up.

If anyone out there has a 3.1, I'd be grateful if they could let me know if my start up sequence matches theirs. The computer seems to function perfectly.

Running 10.6.8, 2 hard drives and 12GB RAM installed.

Many thanks in advance.

[DeltaMac]

Did your old MacPro also have 12GB of RAM installed?

I'm thinking that the logic boards, and the processor cards, are enough different between the two models, that you may have some difference in the boot sequence. For example, the memory bus is very different:
the 2,1 MacPro has dual-channel RAM
the 3,1 MacPro has two branches of dual-channel RAM, which, in effect, gives you double the performance of the memory bus on the 2,1. And, the channels are dual simplex, which means that reads and writes to the memory bus can occur simultaneously.
Big leap in memory performance compared to the 2,1.
I suspect the boot process sets up differently, because of those internal differences.

Anyway, nothing to be concerned about, it's just different.

[Paul P]

Quote: Originally Posted by DeltaMac Did your old MacPro also have 12GB of RAM installed? I'm thinking that the logic boards, and the processor cards, are enough different between the two models, that you may have some difference in the boot sequence. For example, the memory bus is very different: the 2,1 MacPro has dual-channel RAM the 3,1 MacPro has two branches of dual-channel RAM, which, in effect, gives you double the performance of the memory bus on the 2,1. And, the channels are dual simplex, which means that reads and writes to the memory bus can occur simultaneously. Big leap in memory performance compared to the 2,1. I suspect the boot process sets up differently, because of those internal differences. Anyway, nothing to be concerned about, it's just different.

DeltaMac,

thanks for your reply.

The 2.1 had 4GB RAM.

Thanks for helping me out. It would be good to hear from a 3.1 owner, just to confirm.

I appreciate your time.

[DeltaMac]

Ah, well, the extra RAM makes a lot of difference in the initial power on.
More RAM extends the time for the POST (Power On Self Test)

[Paul P]

Quote: Originally Posted by DeltaMac Ah, well, the extra RAM makes a lot of difference in the initial power on. More RAM extends the time for the POST (Power On Self Test)

DeltaMac,

thanks for that.

I suppose it would be easy to pull out one of the RAM trays, and see how that affects the start up sequence. Maybe I should do that.