Adapting an existing PSU to power a hard-drive only setup

[mrbones]

Not sure where to post this, since this is sort of a mix of modding, HDD and PSU but I figure since the deciding factor here is the PSU I'll post the thread here.

I'm thinking of creating my own DIY case/enclosure to power several HDDs (not solid state) that will be used periodically for backups. To keep things simple let's say I won't leave them on ad infinitum. That is, turn system on, do my backups, power off. To power them I would like to use an ATX power supply (no info on the specs yet, I'm holding out on buying one until I know that this is possible... or not). The catch here is that I want to do this without a motherboard.

I've heard it's possible to short the green wire with a ground and wire that to a switch to turn the power supply on/off as needed. Yeah I know, I'm late to the party. Never really messed with electronics until recently. Is this a reliable, stable way to power the hard drives? Does there exist an already better established alternative to this sort of design?

Even though I've seen some powered HDD docks with Sata/usb outs for sale I'm concerned with the longevity of those units and am inclined to find a DIY solution. Besides it just makes it more fun. Thanks for your help.

 

[UltraTaco]

I think it's not worth the effort, just get an external drive, or get a drive caddy.
Shorting green and ground works, but nt sure if it's good for drive to power it off that way..I guess it shouldn't be a problem. Since external drives just power off that way. You probably dont want to use write caching when doing it this way

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[Janus67]

https://www.microcenter.com/product/290245/hddrack5-5-bay-hard-drive-rack

I use one of those next to my server when I ran out of drive bays inside.

 

[mrbones]

Thanks for the replies fellas,

Ultra Taco, the reason I'm shying away from externals is because I don't want to end up in a situation where I have multiple drives that need to be taken out and stored away again every time I need to do a backup. That said I do own an external right now and have no problems with it as far as its performance. I'm just looking for a "set and forget" type of setup. Thanks for the tip about write caching, I just looked it up and it would make perfect sense to disable that in case of an impromptu failure.

I also have 2 quite curious cats dwelling in my room, so that drive caddy is at the mercy of their uncanny ability to knock anything and everything standing over But it's a good solution otherwise.


Janus67, nice find! That rack looks like the very thing I'm trying to build from scratch, except the drives would be mounted in a case. Even comes with that ATX switch that I would have to wire myself. How is your experience with the unit so far? Doesn't look like much can go wrong here.

 

[Janus67]

It works well for my needs. Sits on a wire shelf/rack next to my server. I have the PSU plugged into it with the SATA cables going into the drives and I have breakout HBA cables coming out of my PCI-E slot on the case going directly to the drives.

 

[mrbones]

Sorry for the late bump

I've been doing a fair bit of research on achieving the setup described above, and to give an update I've ended up going with the separate power supply + hard drive option. I bought 2 cheap hard drives, and a new power supply (EVGA BR 500W) to test the implementation of this plan. Yeah I know the PSU is a bit overkill for what I have going on, but at least it can be used in the future to power a full system. Shorting pins 13/14 with a stripped copper cable worked like a charm. At first I was doubtful it worked, but turns out that specific PSU doesn't power on all of its fans unless it detects a certain load threshold. What that is I can't recall at the top of my head. Regardless the drives powered on without a hitch which made me pretty happy after a bit of an anxious waiting period!

I suppose the reason for my choice is knowing that PSUs are fairly bulletproof. Everything fails at one point or another but a PSU seems like a safe bet. Now all I have left is to pick out a case for the build and solder an additional power switch using the wires corresponding to the ps_on and GND wires.

Either way, I appreciate the help given in the thread. Like I mentioned that drive bay rack is a really neat design. Had I not been so stubborn I may have gone for it, but alas that's just my personality coming into play

No promises yet, but I would be happy to post pictures of the completed build once I get to it. Cheers!