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Psu that can handle 40Amps at system start?

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Commander_Kang

Speedy Dragon
Joined
Mar 4, 2001
Location
MD
I need some power supply help on my project here
http://forum.oc-forums.com/vb/showthread.php?s=&threadid=163020
It currently looks like my setup will pull close to 40 amps at start up.What I'm trying to decide is should I get one big beefy psu that can handle 40 amps at start up or have two mid range psus,one for every 4 drives.
I'm currently looking at buying 2 Enermax EG301P-VB PSUs.They can handle 22Amps each.
 
22 amps of what? 5v? 12v?

PS-Enermaxs are lightweights as far as maximum output is concerned, consider Fortron/Sparkle 350's or Antec True Power 380's (or perhaps one Fortron or Antec 550...)
 
As well, many large scsi drives have a start up delay you can use so only half of the drives spin up at one time, lessening the peak load on the supply.
 
The 300W Enermax you listed is rated at 15 amps on the 12V, not 22. Regardless of rating they are left in the dust by a 300 Fortron. Here are the rated 12V outputs of the top supplies, as you can see 40A is hard to come by. I would recommend using a 350W Fortron in conjunction with the start up delay on half the drives to distribute the start up load over time.

Fortron 12V output
-------------------
300W 15A
350W 16A
400W 15-16A, depending on model
460W 16.5A CPU/15A IO
FSP550-60PLN 18A CPU/18A IO
FSP550-60PLG 36A

Antec True Power 12V output
----------------------------
330W 17A
380W 18A
430W 20A
480W 22A
550W 24A

The FSP 550-60PLG model is designed for the application you have in mind, with a small 150W 3.3+5V output but a whopping 36A 12V output. Full specs on the various Fortron models are found at: http://www.fortron-source.com/images/DM(PC)2003-1.pdf

The 550W Forton sold by directron is the PLN model, not much better for your application than the 350 (unless you re-wire it to take advantage of both the CPU and IO outputs). As mentioned staggering the startup events via the delay setting is highly advisable.
 
Thanks for all the input larva.Looks like I'll be buying the Fort 350.
Just looked up the delay on the drive,its 12 secounds should do the trick.O also is there any way for me to make a power switch for the psu so I can power the psu up with out a mother board.?
 
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Yes, just use the paper clip trick, but use a switch to make the connection between the appropriate pins rather than a paper clip.

I suspect the Fortron 350 will do fine, but if it is overwhelmed you can always get a second one. Still cheaper than any of the 550W supplies. Two Fortron 350's will power a small city, but with the startup delay on half the drives one will probably do the trick.
 
The 550watt Enermax has 36amp on the 12V rail, not that I'd recomend an Enermax to anyone 'cept Sadam Hussien maybe? :) ...
 
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