hard drive power sequencer, hard drive startup sequencer

[Timothy Daniels]

Does anyone make a power sequencer that
could be used to startup hard drives sequentially
rather than all at once? I'd like to put 4 HDs
in my PC, and I don't want to load the power
supply with spinning up all 4 HDs at the same
time.

*TimDaniels*

 

[Eric Gisin]

For IDE drives? Nope, can't be done.

They only draw 2A @ 12v, so you only need a 250W power supply.

| Does anyone make a power sequencer that
| could be used to startup hard drives sequentially
| rather than all at once? I'd like to put 4 HDs
| in my PC, and I don't want to load the power
| supply with spinning up all 4 HDs at the same
| time.
|
| *TimDaniels*

 

[Hiawatha Bray]

Dumb question, but...why?

 

[Timothy Daniels]

"Hiawatha Bray" asked:

Dumb question, but...why?

Why what?

*TimDaniels*

 

[Overlord]

I spin up 8 SCSI drives in this system. I can jumper them to spin up
at so many seconds times the drive ID (which I don't like) or set them
up to spin up sequentially when each gets the right signal from the
SCSI controller at the end of the post. Don't know of anything that
will do that with IDEs tho, sorry....

Does anyone make a power sequencer that
could be used to startup hard drives sequentially
rather than all at once? I'd like to put 4 HDs
in my PC, and I don't want to load the power
supply with spinning up all 4 HDs at the same
time.

*TimDaniels*

~~~~~~
Bait for spammers:
root@localhost
postmaster@localhost
admin@localhost
abuse@localhost
postmaster@[127.0.0.1]
~~~~~~
Remove "spamless" to email me.

 

[Tom]

raid 0,1 would be one reason for 4 drives

Dumb question, but...why?

 

[Rod Speed]

Does anyone make a power sequencer that could be used
to startup hard drives sequentially rather than all at once?
I'd like to put 4 HDs in my PC, and I don't want to load the
power supply with spinning up all 4 HDs at the same time.

No need for anything special with 4 IDE drives.

Just use an adequate power supply.

If the power supply isnt adequate, replacing it with a bigger
supply would be a lot cheaper than a power sequencer.

 

[Timothy Daniels]

My Dell Dimension's PSU is rated at 200w.
I'm worried that a voltage sag due to 4 HDs
spooling up simultaneously might impact
something negatively. The subject of HD
power up sequencig came up when Barry
O'Grady said in
comp.sys.ibm.pc.hardware.storage on
August 15th that he had such a sequencer.

*TimDaniels*

 

[Timothy Daniels]

No need for anything special with 4 IDE drives.

Just use an adequate power supply.

If the power supply isnt adequate, replacing it with a bigger
supply would be a lot cheaper than a power sequencer.

That sounds like good advice, and that may be the only
practical solution. One problem generated by that, though,
is that Dell's motherboards and power supplies do something
weird (I'm not sure what) with the pinout in the connector
(and perhaps with the connector as well) to make their PSUs
and mobos proprietary. And power sequencing has an extra
coolness factor that I can't ignore.


*TimDaniels*

 

[Timothy Daniels]

My Dell Dimension's PSU is rated at 200w.
I'm worried that a voltage sag due to 4 HDs
spooling up simultaneously might impact
something negatively....

OK, I see PC Power & Cooling has 275w
and 300w Dell replacement PSUs now for $89.
That may or may not be cost effective - the
Dell PSUs are reputedly very underrated,
and a 200w Dell PSU is supposedly the
equivalent of 3rd party PSUs rated at 250W
to 300w. If I can get a power sequencer for
the same or less money, I'd rather go with
with the sequencer.

*TimDaniels*

 

[Rod Speed]

OK, I see PC Power & Cooling has 275w
and 300w Dell replacement PSUs now for $89.
That may or may not be cost effective - the
Dell PSUs are reputedly very underrated,
and a 200w Dell PSU is supposedly the
equivalent of 3rd party PSUs rated at 250W
to 300w. If I can get a power sequencer for
the same or less money, I'd rather go with
with the sequencer.

Mad, and they dont exist anyway.

 

[Rod Speed]

That sounds like good advice, and that may be the only
practical solution. One problem generated by that, though,
is that Dell's motherboards and power supplies do something
weird (I'm not sure what) with the pinout in the connector
(and perhaps with the connector as well) to make their PSUs
and mobos proprietary. And power sequencing has an extra
coolness factor that I can't ignore.

Its unlikely to work, the bios will have given up on the drives.

 

[Timothy Daniels]

Mad, and they dont exist anyway.

That's me - if they don't exist,
look harder.


*TimDaniels*

 

[Timothy Daniels]

Its unlikely to work, the bios will have given up on the drives.

You know, that's interesting. What does the BIOS do
while it's waiting for the Master hard drive to spool up?
I mean, there must be a wait involved since it starts up
immediately up application of power while the hard drive
takes several seconds to come up to speed. There must
be a signal from the hard drive that tells the BIOS that it
can proceed with the boot strap loading. It would seem
that it wouldn't be too hard to extend that wait until all the
hard drive spool-ups have completed before proceeding.


*TimDaniels*

 

[Rolf Blom]

You know, that's interesting. What does the BIOS do
while it's waiting for the Master hard drive to spool up?
I mean, there must be a wait involved since it starts up
immediately up application of power while the hard drive
takes several seconds to come up to speed. There must
be a signal from the hard drive that tells the BIOS that it
can proceed with the boot strap loading. It would seem
that it wouldn't be too hard to extend that wait until all the
hard drive spool-ups have completed before proceeding.


*TimDaniels*

Depends on what BIOS you are using; you should wait for IDE master/slave
negotiations to complete. If the drives don't power up at roughly the
same time, this negotiation fails, and you may only see a single drive
on each IDE cable. (or none, in some odd situations)

Powering all +5V immediately, and only delaying +12V, would likely
result in diagnostic errors in the drives own firmware, and possibly
cause the drive to have random lockups at boot, unless the internal
logic is designed with power sequencing in mind.

Ask the drive manufacturer directly, and see what they say.

SCSI is much better at this than IDE, since SCSI drives have a motor-on
command that lets the controller start up the drives in sequence.
(it usually requires a drive strap setting + controller configuration)

/Rolf

 

[Folkert Rienstra]

Depends on what BIOS you are using; you should wait for IDE master/slave
negotiations to complete. If the drives don't power up at roughly the
same time, this negotiation fails, and you may only see a single drive
on each IDE cable. (or none, in some odd situations)

Powering all +5V immediately, and only delaying +12V, would likely
result in diagnostic errors in the drives own firmware, and possibly
cause the drive to have random lockups at boot, unless the internal
logic is designed with power sequencing in mind.

Ask the drive manufacturer directly, and see what they say.

SCSI is much better at this than IDE, since SCSI drives have a motor-on
command that lets the controller start up the drives in sequence.

IDE has that too since ATA/ATAPI-5.

 

[Rod Speed]

Rod Speed wrote

That's me - if they don't exist, look harder.

That wont exist if there is no market for the product.

And it wouldnt work anyway, the motherboard bios will have given
up looking for hard drives by the time the last one is powered up.

 

[Rod Speed]

Rod Speed wrote

You know, that's interesting. What does the BIOS do
while it's waiting for the Master hard drive to spool up?

It basically interrogates the drive on its details. Since the
drive is powered up and is itself waiting till the drive spins
up, it works fine. The bios doesnt wait forever and its very
unlikely indeed to still be polling for drives at the time that the
last drive of the 4 has been powered up by a power sequencer.

I mean, there must be a wait involved since it starts
up immediately up application of power while the hard
drive takes several seconds to come up to speed.

Yes, but the drive electronics is obviously up and it can
take a second or so to reply to the request for its details.

There must be a signal from the hard drive that tells the
BIOS that it can proceed with the boot strap loading.

Not really. Initially the bios interrogates the drives on
their capabilitys, as part of the AUTO config mechanism,
and once its determined what drives are connected, then
just reads the MBR off the drive its been told to boot off,
identifys the partition to boot from and starts doing that etc.

It would seem that it wouldn't be too hard to extend that wait until
all the hard drive spool-ups have completed before proceeding.

Yes, there isnt any technical reason why say you
couldnt specify in the bios to allow say 10 secs for
all the drives to have spun up, but few bios have that.

Makes a hell of a lot more sense to just get a better
power supply instead of farting around like that, and
thats why few bios have anything like that.

SCSI drives do have that capability, and the
bios on the SCSI card allow for that capability.

 

[Arno Wagner]

"Rod Speed" wrote:

[...]
Depends on what BIOS you are using; you should wait for IDE master/slave
negotiations to complete. If the drives don't power up at roughly the
same time, this negotiation fails, and you may only see a single drive
on each IDE cable. (or none, in some odd situations)

Powering all +5V immediately, and only delaying +12V, would likely
result in diagnostic errors in the drives own firmware, and possibly
cause the drive to have random lockups at boot, unless the internal
logic is designed with power sequencing in mind.

Ask the drive manufacturer directly, and see what they say.

SCSI is much better at this than IDE, since SCSI drives have a motor-on
command that lets the controller start up the drives in sequence.
(it usually requires a drive strap setting + controller configuration)

Some older IDE drives had an disable-aito-spin jumper. This
is not quite the same as sequenced spin-up, but might serve
as well. Unfortunatetely this jumper seems gone today.

Arno

 

[Barry OGrady]

That wont exist if there is no market for the product.

And it wouldnt work anyway, the motherboard bios will have given
up looking for hard drives by the time the last one is powered up.

I have a card that is used for that purpose. It connects in line with the
power to a drive and delays the feeding of power on startup.


-Barry
========
Web page: http://members.optusnet.com.au/~barry.og
Atheist, radio scanner, LIPD information.
Voicemail/fax number +14136227640