6 HDDs in MDD

MatthewLTL

macrumors 68000
Original poster
Jan 22, 2015
1,684
18
Rochester, MN
I was just cerious, Would it be Ideal or wise to make the MDD have 6 HDDs by using 2 HDDs (with 5.25-3.5 brackets) on the ATA33 bus in place of the Optical Drives?

Out of testing the system I even booted Leopard with my HDDs hooked to the ATA33 bus and it didn't seem much slower.

Any thoughts?

Also anyone try 12 HDDs? 12 2.5 drives inside dual 3.5-2.5 brackets?
 

Intell

macrumors P6
Jan 24, 2010
18,872
368
Inside
There is no reason why you can't safely run it with 6 hard drives. You could run it with 12 as well, but you'd need a PCI interface card for 6 of them.
 

Altemose

macrumors G3
Mar 26, 2013
9,089
444
Elkton, Maryland
Keep in mind that the PSUs on these machines were designed to drive large ADC monitors with accompanying USB devices attached over the AGP slot. So the draw of hard drives is not an issue.
 

Intell

macrumors P6
Jan 24, 2010
18,872
368
Inside
Keep in mind that the PSUs on these machines were designed to drive large ADC monitors with accompanying USB devices attached over the AGP slot. So the draw of hard drives is not an issue.
The ADC displays are on a different 24V rail than that of the 12 and 5 volt drives.
 

Intell

macrumors P6
Jan 24, 2010
18,872
368
Inside
It would appear that iBooks' lack of a PRAM battery is my legacy in the PowerPC section of MacRumors.
 

poiihy

macrumors 68020
Aug 22, 2014
2,273
40
when you hook a fan up to the 5V and 12V lines its 7V power. Does this mean that HDDs are in fact, 7V or are they 17V?
The HDDs use the 5v and 12v rails separately. An HDD could use 7 volts if it wants but I don't know of any HDD using 7 volts.
 

Intell

macrumors P6
Jan 24, 2010
18,872
368
Inside
As poiihy and Altemose have said, hard drives use both voltages and the clock and other settings are kept by the main battery and the small capacitor.
 

poiihy

macrumors 68020
Aug 22, 2014
2,273
40
iBooks and 12" PowerBooks have a small capacitor which stores PRAM information rather than a battery. This is kept charged by the main battery.
Is that the shot but wide component that looks like it is held in by a holder instead of soldered in, like a battery, but wrapped in blue warp like a capacitor?
 

eyoungren

macrumors Core
Aug 31, 2011
21,178
13,012
ten-zero-eleven-zero-zero by zero-two
iBooks and 12" PowerBooks have a small capacitor which stores PRAM information rather than a battery. This is kept charged by the main battery.
As poiihy and Altemose have said, hard drives use both voltages and the clock and other settings are kept by the main battery and the small capacitor.
But now I have been reminded :)
 

MatthewLTL

macrumors 68000
Original poster
Jan 22, 2015
1,684
18
Rochester, MN
what was the point of the 3.3V line added to SATA connectors? and i have always wondered why are SATA HDDs 25pin power when the connectors are only 4 or 5 wires?
 

poiihy

macrumors 68020
Aug 22, 2014
2,273
40
what was the point of the 3.3V line added to SATA connectors? and i have always wondered why are SATA HDDs 25pin power when the connectors are only 4 or 5 wires?
3.3v line is probably for newer technologies. No known HDD uses the 3.3v line but maybe SSDs use them.

SATA power plugs have many pins because they need multiple pins for power because one pin is too small. I think each power wire uses 3 pins or something like that. Also a few more pins are used for hot-plugging technologies.
http://superuser.com/questions/98274/why-are-there-so-many-pins-on-a-sata-power-connector
 

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