minimum power supply watage?

[George Hester]

Windows XP
PII dual Processor
Floppy drive
3 IDE harddrives ATAPI
2 UW SCSI harddrives
CD-ROM

 

[philo]

Windows XP
PII dual Processor
Floppy drive
3 IDE harddrives ATAPI
2 UW SCSI harddrives
CD-ROM

i recently did some current-draw tests on a similar machine...
and the initial surge on those UW SCSI's is rather high.
my machine has a 400 watts supply...
but you may be able to get by with a good quality 300 -350 watt supply

 

[Colon Terminus]

A good 350 watt supply should be more than sufficient.

 

[Rob Stow]

A good 350 watt supply should be more than sufficient.

Even a good 200 W unit would be probably be enough, depending on
the processors. PII's need from 18 to 43 W. The drives need 10
to 18 W each. No more than 30 W for everything else.

FWIW, I built this for someone about three years ago:
- Tyan S2446 dual Socket A motherboard
- Two AMD Duron 1300 MHz
- 4 x 256 MB PC2100
- 6 x 80 GB IDE, RAID 5, with 3Ware controller
- 2 x 40 GB IDE, RAID 1, with second 3Ware controller
- CD-ROM
- 250 W Enermax PSU

The 3Ware controller staggers the spin-ups of the drives attached
to it - without enabling that feature the PSU could not cope.

All of the hard drives in the RAID 5 have since been replaced
with 200 GB drives, but that old PSU still keeps chugging along.

 

[George Hester]

It did work with a 250 last night. Woke up this morning and the second SCSI
wasn't found. I keep having to remove IDEs reset Master Slave get it
working put it back together full. It's working. Turn it off eat a cracker
come back don't work no more. This is too much. I have a good 300 with
noise reduction but that might not even be enough.

 

[George Hester]

Mine (250) copes off and on. Copes at Midnight but not at Noon. And I'm
not kidding.

--
George Hester
_______________________________

A good 350 watt supply should be more than sufficient.

Even a good 200 W unit would be probably be enough, depending on
the processors. PII's need from 18 to 43 W. The drives need 10
to 18 W each. No more than 30 W for everything else.

FWIW, I built this for someone about three years ago:
- Tyan S2446 dual Socket A motherboard
- Two AMD Duron 1300 MHz
- 4 x 256 MB PC2100
- 6 x 80 GB IDE, RAID 5, with 3Ware controller
- 2 x 40 GB IDE, RAID 1, with second 3Ware controller
- CD-ROM
- 250 W Enermax PSU

The 3Ware controller staggers the spin-ups of the drives attached
to it - without enabling that feature the PSU could not cope.

All of the hard drives in the RAID 5 have since been replaced
with 200 GB drives, but that old PSU still keeps chugging along.

 

[George Hester]

Alright I put the 300W ATX300GT in:

http://www.home2000.net/client/fspgroupusacom/proddetail.asp?linenumber=191

Seems to be fine. I still have to load the rest of the IDEs to see if that
helps the system be more reliable.
But prior to this I am noticing something else. I am getting a high-pitched
whining noise from I think the front of the machine. It's not easy to tell
but I suspect the SCSIs. I can remove them and be sure and probably should
do that. These SCSIs are Micropolis 9 GB harddrives:

http://www.drivermuseum.com/files/utils/hd_u.html

http://www.sunmanagers.org/archives/1996/0914.html

Can anyone suggest a better SCSI it is UW SCSI where I have 80 to 68 pin
conversion boards that plug into the harddrives. I really do not like this
setup. Those boards a strong wind they could fall right off. Seems to me
there ought to be mounts for those conversion boards. Their only claim to
sturdiness is where they plug into the SCSI and that connection is not deep.

 

[Rob Stow]

Mine (250) copes off and on. Copes at Midnight but not at Noon. And I'm
not kidding.

A *good* 250 W PSU shouldn't have any problem with your system
unless you stuck a high-power video card in it. A cheap 250 W
PSU, however, could be flaky with half the load.

As well, if this midnight/noon flakiness is a verifiable
recurring phenomenon, then it might be a good idea to monitor the
power at the wall outlet.

 

[William Asher]

George Hester wrote:

Can anyone suggest a better SCSI it is UW SCSI where I have 80 to 68
pin conversion boards that plug into the harddrives. I really do not
like this setup. Those boards a strong wind they could fall right
off. Seems to me there ought to be mounts for those conversion
boards. Their only claim to sturdiness is where they plug into the
SCSI and that connection is not deep.

Do you get strong winds blowing through your computer case? I have
several of the LVD-to-68-pin adaptors on disks in rack-mount computers that
fly around in airplanes and they did seem flimsy at first. However,
they've never come loose, but then I don't mount them out on the wing where
there's a breeze.

 

[George Hester]

No, no winds really just my attempt to give you some idea of my lack of
confidence in their sturdiness. Definitely not an IDE cable level
sturdiness.

 

[George Hester]

Well I think it definitely needed a 300W Power Supply. But I'm thinking now
I need more. My second SCSI is not being seen at the boot scan but appears
fine once the Op sys is up and running.. That sounds Power Supply don't it?