using 2 power supplies in the same case

[allister]

hi is there anyway i can get a second power supply to switch on when i power up the pc and switch off when it goes off. I have 2 new 550 watt psu's and want to use one for the mobo,fans and the other for the hard disk drives ( all 10 of them ). reason for this is i keep burning power supplies and am fed up of buying new ones.

thank you in advance

allister

 

[edfair]

YOu keep 10 drives on a power supply and you will probably replace it pretty soon too. There are limits to the current supplies within the power supply.
You don't need a 550 that has CPU voltages, you need an AT type with +5 and +12 that you can control through a relay.

Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[allister]

thanx but was thinking more along the lines of splicing a wire maybe the one that gets the psu to start and stop

 

[dakota81]

Don't know what type of drives you have, some SCSI harddrives have jumper settings to delay their spin-up time to alleviate the power surge on the psu.

 

[micker377]

Probably a waste of time, but if you really want to do it - wire up a 12 volt relay to one of the "drive" plugs to turn on 120 volts to the other power supply (ATA type).This will turn off and on with the start up of the main ATX PSU. I hope the computer is disposable!

 

[laMagra]

You can connect pin 14 and pin 5 to and external momentary switch or your existing power switch, ether will do.
You might have to connect pin 8 on both PSU's together to get the full power rating on the external rails.

http://modecideas.com/faq42.htm

If you are using the amount of drives that you say you do it sounds like that you are exceeding your PSU's power output. (A common factor of power supplies burning out) You check this by adding the 12v and the 5v ratings from your drives together. The total numbers should be less or equal to the ratings on the power supply

 

[ceh4702]

The problem is you have to have a case designed so you can install separate power supplies. Separate power supplies have to be linked together, because a power supply needs a load or some special adapter to work without a load. They make some server cases designed for multiple power supplies. Sometimes as much as 3 of them. 10 hard drives is an awful lot at spin up. If they were SCSI, I might suggest an external enclosure with a separate power supply or possibly some network attached storage like a dedicated file server. There might be some definite advantage to using high capacity drives to limit their number.

If you do not like my post feel free to point out your opinion or my errors.

 

[GOLCPL]

And also what kind aof PSU are you using? That alone can be the Problem

 

[allister]

GOLCPL : they are 2 x 550 watt atx psu's

laMagra thanx for the link i read this : PW-OK Receives power fed back from the motherboard and the power supply then senses whether it's getting a normal voltage... Should be 3-5 volts. If not then the PSU is bad. That is the pw_ok signal that tells the board that +3.3, +5, and +12 are within tolerance and that the PSU is ready for full start-up. Note: It doesn't generate a voltage; it senses one.
so if you join the PW-OK wires fron the main supply and the spare psu will that not switch it on and off ??

 

[laMagra]

Your almost there, the PW-OK connection is more like a heart beat sensor than an on switch. All you have to do is connect the PW-ON (pin 14) to any ground connector (pin 3, 5, 7,13,15,16 and 17) for the power supply to start up. Once this has happened the PSU senses the signal from the M Board to carry on producing power. (This is a fail safe) You don’t want the PSU to carry on producing power if the system is faulty.

 

[allister]

so can i connect the PW-ON (pin 14)from my (slave) psu to any ground connector (pin 3, 5, 7,13,15,16 and 17) for the power supply which is connected to the motherboard ?

 

[GOLCPL]

I'm sorry if my Question was not understood. I meant What Brand?

 

[sixstrings4]

Why not just set up two systems with 5 drives apiece and network them together? Your second system wouldn't have to be top of the line...just barebones enough to run.

 

[Grenage]

http://www.procooling.com/articles/html/linking_multiple_psu_s_as_one_.php

http://pc-mod.com/articles/atx/

What I did a fair few years ago in a large case was link a seperate power supply to large Sunon and Delta fans and cross the correct pins on a dip switch. When the weather was too hot I could then turn on the fans independently.

Looking back however I would never do that again.

 

[AnalogAnomaly]

I have a file-server with 10 hard drives as well. I use a zippy 700 Watt EPS power supply that i've attached an atx adaptor to. the over-head covers spin-up just fine. though i wouldn't say.. run it on a high-draw board.. you're more than likely looking at using it on a single-cpu system unless you want to cut back on hard-drives. This solution however is quite costly.. around $400 The only machine i've spent more money on is my godbox. Also, i would hope that you have good airflow through the machine. I personally recommend sunon double ball bearing fans. They move so much air i've had to get out the tin-snips from time to time to stop cases from whistling.