Seagate 750's in a 9-bay FireWire enclosure?

External Since: Oct 30, 2007 Posts: 1

Did anyone succeed to fill a 8 or 9 bay HD enclosure with Seagate
750's and got them all to work?

I had until now 5 of these 750s working in my enclosure... two per
FireWire port as master / slave pairs, the last lonely HD set to
master. The rig worked like a charm.

But now that I'm trying to add the next 2 Seagate 750's following the
same system, for a total of seven - no dice. One of more of the HDs
always vanishes. Formatting of the new drives fails. Swapping cables
and FireWire ports solves nothing.

Did anyone run into the same problem, yet? Was there a solution?

My only hunch for now is that perhaps the 300 Watt power supply in my
enclosure is too weak to run more than five 750 Giggers along with
their 10 cooling fans, hence all these weird problems, caused by power
fluctuation. Perhaps i should plug a voltmeter into one of the
remaining empty HD power plugs and measure what I get, as compared to
the Seagate's +5V 0.72A and +12V 0.52A specs, printed on the label?
(Then again, it's only a hunch...)

Grateful thanks for all helpful suggestions in advance

George

External Since: Jul 14, 2003 Posts: 927

In article ,
George K. wrote:

> But now that I'm trying to add the next 2 Seagate 750's following the
> same system, for a total of seven - no dice. One of more of the HDs
> always vanishes. Formatting of the new drives fails. Swapping cables
> and FireWire ports solves nothing.

do you have top quality firewire cabling?

> My only hunch for now is that perhaps the 300 Watt power supply in my
> enclosure is too weak to run more than five 750 Giggers along with
> their 10 cooling fans, hence all these weird problems, caused by power
> fluctuation.

that's my first guess.

> Perhaps i should plug a voltmeter into one of the
> remaining empty HD power plugs and measure what I get, as compared to
> the Seagate's +5V 0.72A and +12V 0.52A specs, printed on the label?
> (Then again, it's only a hunch...)

that's not spin-up power. i can't find the spec for spin-up power for
that drive at seagate.com but i checked a hitachi drive and it needed
+12v @ 2a and +5 @ 1.2a. that's 30 watts right there, times nine
drives is 270 watts, plus the fans, so a power issue is quite likely.

can you stagger the spin-ups so it doesn't tax the power supply?