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Choppaface

macrumors 65816
Original poster
Jan 22, 2002
1,187
0
SFBA
I was wondering if anybody might be able to give me some help on this issue... I've done a lot of searching but haven't found anything conclusive yet..

Does anybody know if the intel chipset in the mac mini supports SATA port multiplier? I was thinking of hooking up a mini to this:

http://www.addonics.com/products/host_controller/ad5sapm-e.asp

(power form an alternate PSU, not from the mini)

From what I read the chipset in the mini should support SATA 2, which also should include port multiplier (PM) support (?), but Apple only ships the mini with a SATA 1 drive so I'm not sure.

Are there any intel chipset buffs out there that could gimme a hand? :) thanks!
 

WeekendSailor

macrumors newbie
Sep 16, 2006
2
0
Dallas (Tx) area
Unsure If Mac mini SATA Controller Is Port Multiplier Capable

Hello;

I know that your posting is old (I'm writing this on Sep 16, 2006) but your question is exactly one that I've been asking myself for about the past week (ever since I managed to install 2 GB RAM in my new Intel Mac mini and found that it wasn't that difficult mechanically) ..... Is the Intel Mac mini SATA Controller Port Multiplier compliant ?

Well I don't have the answer but I will comment that when reading the Intel Mac mini's Developer's notes it says that the SATA Controller is a Intel AHCI 1.1 device.

When I then go to read the AHCI 1.1 specs I'm left with the feeling that the Intel Mac mini MAY have a Port Multiplier capable SATA Controller but nothing definitive.

I need to go back and read the AHCI 1.1 spec over two-or-three times to see if I can understand what it says (trying to understand something by reading its spec is almost always a painful experience).

So far my best estimate is that the Intel Mac mini's SATA
Controller MAY have the ability to work with a Port Multiplier but I think that there are registers that have to be configured (i.e. 'turned-on') to signal to a Port Multiplier that it (the mini's SATA Controller) is capable. Also there is probably a 'layer' of software (a 'driver') needed to provide the interface to multiple SATA drives (through an external SATA Port Multiplier).

So there are at least two of us asking the question about the Intel Mac mini's SATA Controller ..... does anyone have more definitive information on whether-or-not it can be run with an external SATA Port Multiplier ?
 

Faraday

macrumors member
Mar 25, 2004
38
6
Melbourne Australia
Answer is no.

The Intel Mac Mini SATA port does not support port multipliers.

Apple are using the 945GM chipset in the Mac Mini.

This chipset uses a mobile version of the Intel 82801(GBM) as the southbridge, which supplies the SATA functionality.

The Intel datasheet for this chip shows that the SATA posts don't support port multiplier operation (pp 506, section 12.3.1.1)

It also shows that the Mac Mini SATA ports are limited to SATA I 1.5 Gbps speeds rather the 3.0 Gbps SATA II speeds, despite Apple referring to it supporting "advanced SATA-II features" in the developer docs. They are technically correct however, as the SATA ports do support NCQ which is a SATA II feature, and this is enabled on the stock 5400 rpm drives.

One interesting possibility does arise though. This southbridge chip supports two SATA channels, though Apple have brought out only one SATA connector on the HD riser card. The second SATA port is enabled/disabled by the BIOS/EFI at boot. I wonder if the second port is left enabled, is available on the HD riser card, but just doesn't have a connector provided ??. A second SATA channel would allow for some seriously quick striped Raptor action....
 

flir67

macrumors 6502
Jun 23, 2005
256
0
owwweee, you mentioned raptor on a mini, that got my attention. LOL
:D

those drives rock, had the 36gb years ago.freakin amazing drive. was a constant gamer on pc then ,
;)
 
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