Jump to content


Photo

Sata power (orange/3.3v) question


  • You cannot start a new topic
  • Please log in to reply
9 replies to this topic

#1 anywhere

anywhere

    Member

  • Member
  • 91 posts

Posted 26 February 2014 - 10:13 AM

Alright, apologies if mentioned, search with a few keywords didn't pull up anything, and googling my scenario came up with nothing.

Pair of donated sata 500s. Hitachi and a barracuda. Hooked them up to a box, mdadm, played fiddled, etc. Raid 1, whatever, regardless....

Moved them to my torrent box that sits in my buddies uncapped 50mbps pipe, fired it up. Hba saw nothing. Hmmm.

Moved molex to sata power adapter around. Restart. Nothing. Wiggled data cables. Nothing. Unplugged the other 12 drives, fans, and even jammed cpu fan so I had dead silence. Confirmed, they we'remt powering up.

Moved them back to the previous box, flawless boot. Wtf?

Closer inspection, missing the orange on my adapters.

Can a man safely hock 3.3 from somewhere on an older psu? I have soldering iron skills.....

Appreciated, figured this place would be the best to ask. The help here has never let me down.

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro


#2 anywhere

anywhere

    Member

  • Member
  • 91 posts

Posted 26 February 2014 - 10:32 AM

Update

Better re-wording my question, how can I safely supply a 5 wire sata from a 4 wire molex, with the assistance of jumping 3.3 somewhere from the psu?

Psu has a 3.3 supply rail. I think it's safe for 2 hdds.


Sent from my rooted HTC Supersonic using Tapatalk 2 Pro


#3 continuum

continuum

    Mod

  • Mod
  • 3,581 posts

Posted 27 February 2014 - 12:22 AM

Are these 3.5" drives or 2.5" drives? I don't think many (if any) 3.5" SATA drives actually need +3.3v from the SATA power connector...

 

If 2.5" then I'm not as sure (a quick spec sheet check oughta say...)

 

Since you can solder or crimp, well, shouldn't be hard... :P


#4 Mickey

Mickey

    Member

  • Patron
  • 2,281 posts

Posted 27 February 2014 - 01:25 AM

No 3.5" drives use the 3.3V rail (yet). I don't think there are any 2.5" drives that use it, either. At least, I've not come across any in our lab testing. There has been occasional talk about 3.5" drives moving away from using the 12V rail and replacing it with 5V, but no word yet on when that will happen.


#5 anywhere

anywhere

    Member

  • Member
  • 91 posts

Posted 27 February 2014 - 06:13 AM

Well, they physically will not power up unless using the lead/psu With the orange wire.

So I dunno. You say they don't need it, yet they won't spin ubless it's there.



Sent from my rooted HTC Supersonic using Tapatalk 2 Pro


#6 Mickey

Mickey

    Member

  • Patron
  • 2,281 posts

Posted 27 February 2014 - 10:06 AM

That's very strange then, because in a lab w/ over 100+ systems that aren't using the 3.3V rail, I haven't heard of any test drives not spinning up. The only plausible explanations I can think of is:

 

1. Your particular drives need 3.3V (which would be surprising, but I'm not going to say impossible because I haven't seen *every* drive in production :)) Perhaps it's a firmware setting on the drive.

 

2. There's some issue with the legacy Molex to SATA power adapters you're using, such as a loose wire, bad crimp, etc.

 

If it's #1, I suppose you could try tapping a 3.3V source from somewhere, as the 3.3V should only be used for the logic circuits on the board and not driving the motor or VCM (which are much more power hungry).

 

If you have the model numbers, you could look up the manufacturer specs for power draw, which usually split it into the different rail draws. See how much juice it needs.


#7 anywhere

anywhere

    Member

  • Member
  • 91 posts

Posted 27 February 2014 - 10:18 AM

The molex adapters worked on the previous drives so I'm assuming they're still good, unless both broke while unplugging them this last time.

I'm triple stumped, as the Hitachi has a legacy molex, and it still doesn't power up using that.

Both these drives came out of old dish network dvr boxes. And they had the orange supply wadded with the other traditional 4.

I honestly do think it's a necessity, im just double checking if I can steal 3.3 from the 20pin supply and not over amp anything.

I also assumed the 3.3 was a small amp draw.

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro


#8 anywhere

anywhere

    Member

  • Member
  • 91 posts

Posted 28 February 2014 - 09:27 AM

Garh!

I stand corrected on myself. The dish dvr boxes do not have the orange 3.3 supply.

My adapters molex to sata worked OK on other drives, but not these.

For some reason, they will only power up in my one rig with the native 5 wire supply, or a factory dvr box with 5/12/2grnd 4 wire supply. Crazy. I don't know.

I'm out of ideas. this weekend I'm attacking stuff with a soldering iron.

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro


#9 anywhere

anywhere

    Member

  • Member
  • 91 posts

Posted 03 March 2014 - 10:47 AM

Haha, they worked fine the while time! After splicing 3.3 I still had two drives show 0Gb on card bios initialization. So i was angry, drinking my beer, said F'it, and let it finish booting, dmesg piped with grep, for the hell of it. And it showed a pair of 500s! Some reason card shows 0Gb, then once kernel starts poking at them they spin up and register correctly. Must be a firmware thing. Reboot then they show their size on card bios correctly. Shut down system, turn on, zero size again until probed. Jesus, all this cool splice work for nothing. Oh well. Sent from my rooted HTC Supersonic using Tapatalk 2 Pro

Edited by anywhere, 03 March 2014 - 10:52 AM.

#10 jtsn

jtsn

    Member

  • Member
  • 94 posts

Posted 10 March 2014 - 12:42 PM

No 3.5" drives use the 3.3V rail (yet). I don't think there are any 2.5" drives that use it, either. At least, I've not come across any in our lab testing. There has been occasional talk about 3.5" drives moving away from using the 12V rail and replacing it with 5V, but no word yet on when that will happen.

 

It doesn't make any sense to use 3.3 V, it requires higher current on the orange wire for the same power requirement and is more prone to ohmic voltage drop. The 3.3 V provided by PC PSUs is of bad quality, because its only regulated using the sense wire connected to the mainboard ATX connector. So the orange wire is basically useless and nobody uses it.

 

2.5in drives stay with 5V single voltage due to USB using it (where 12 V would have made more sense, but that was wrong design decision, that can't be reverted anymore). For 3.5in drives it would make more sense to move to 12 V single voltage, because converting down from 12 V is more efficient than from 5 V and external enclosures are usually powered this way.





1 user(s) are reading this topic

0 members, 1 guests, 0 anonymous users