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[email at mattruby.com]

I have over a half-dozen different SATA hard drives, each with
different data (configs, voiceprompts, voicemail, CDRs, AGIs) for each
one's different user groups and applications. Each one's load on the
Asterisk server is small enough that one server can host them all,
accessed easily over USB.

But right now, each one is in its own external USB enclosure on a
powered USB hub. I want to combine them all into a single large
enclosure. I tried to use a single PC chassis, leaving the USB hub
inside with the drives screwed into it, and powered from the PC power
supply as internal drives on the proper drive power output plugs. But
without a PC motherboard plugged into the power supply, too, the power
supply won't start up to power the drives.

I don't want to add a motherboard: that costs money, and sucks power,
and is totally unnecessary. I just want to make this gutted PC chassis
power my drives only, and have them connect to the complete PC sitting
next to it via the single USB cable coming out of the drive chassis. How
do I do that?

Is it possible to use the extra, unused floppy power plugs to power
more hard drives, with an adapter? Is it possible to split the existing
hard drive power plugs to each power multiple drives? How many drives
can I split each power plug into? The power supply is a cheap 300W unit,
and the drives draw max under 9W each:
http://www.wdc.com/en/products/products.asp?driveid=311 . So can I power
25-30 of these drives, or at least 10?
--

(C) Matthew Rubenstein

[stotaro at totarotechn...]

On Tue, May 13, 2008 at 10:22 PM, Matthew Rubenstein <email at mattruby.com> wrote:

[email at mattruby.com]

On Tue, 2008-05-13 at 22:46 -0400, Steve Totaro wrote:

[cwallace at lodgingcom...]

At 11:45 PM on 13 May 2008, Matthew Rubenstein wrote:

[asterisk at coltect.no...]

If I understand right, your problem is that the power supply won't turn on ?
ATX power supplies can be told to turn on by jumpering 2 pins on the
motherboard power connector. From memory its the Green wire and one of the
black wires, I usually use the next one inwards. Pinouts for the connector
can be found via Google.
If the power supply also has an external on/off switch you can jumper these
pins and use the switch to turn the power on or off.

Hope this helps,
Col

----- Original Message -----
From: "Matthew Rubenstein" <email at mattruby.com>
To: "Asterisk -Users" <asterisk-users at lists.digium.com>
Sent: Wednesday, May 14, 2008 12:22 PM
Subject: [asterisk-users] No-mobo PC for USB Drives Enclosure?

[Alex.Lopez at OpSys.com]

To turn on an ATX power supply that isn't connected to a motherboard use
a wire or paper clip to short the green wire (PS_ON) to any one of the
black wires (COM).

Pins 14 and 15....

Now that's the cheapest solution I can give you....

Alex

Snip...

If I can just

[email at mattruby.com]

On Wed, 2008-05-14 at 14:06 +1000, Col Ferguson wrote:

[joakimsen at gmail.com]

This will work:

http://www.newegg.com/Product/Product.aspx?Item=N82E16899705001

I assume you have devised a way to power the USB to serial adapters
from the PC power supply.

FWIW I think your system is inefficient but maybe you do need 750gb
per each installation. Each to his own.....

On Tue, May 13, 2008 at 10:22 PM, Matthew Rubenstein <email at mattruby.com> wrote:

[skoroneos at digital-o...]

As people have sugested the ATX power supplies can work without a mobo
One thing to watch out for your setup is the actual ampere requirments for
your disks
i.e Your power supply provides 300W but this is "partitioned" to different
voltages (+5, +12, etc) with different amp charecteristics
Disks need 2 voltages. One for the logic (+5V) and one for the motors (+12V)
and have different current requirments.
Most disk (if not all) mention these ratings on the labels they have
What you must do, is to see if by adding the current requirments seperatly
for +5V and +12V, does not exceed the power supply's amp rating *for that
voltage*, allowing also for a 15% -20% margin, as power consumption will be
higher than the nomimal mentioned during disk startup (and you will be
starting all your disks at the same time)
Also make sure your box has sufficient cooling and there is some short of
airflow over the disks, as the number 1 enemy of disks is high temperature
and stacking so many disks in a box will create large amounts of heat.

I would suggest you to get a good (aka expensive) 500W power supply and use
10-12 disks with it to avoid problems in the long run,
Also keep in mind that MTBF specs of SATA disks does not make them an ideal
candidate for 24/7/365 operations

Stelios S. Koroneos

Digital OPSiS - Embedded Intelligence
http://www.digital-opsis.com

[atis at iq-labs.net]

On Wed, May 14, 2008 at 10:41 AM, Stelios Koroneos
<skoroneos at digital-opsis.com> wrote: