Sata 5 pin and 4 pin cables the same?

Feneant2

Golden Member
May 26, 2004
1,418
30
91
Ok... so my brother received a new pc and on it, the sata power cable from the power supply is broken (the plastic top is cut off so it falls when you plug it in- it dangles basically). He does have some molex to sata connectors that work when we try. The only noticeable difference is that the sata power cable from the power supply has a 5th cable, an orange 3.3 volt wire. The other molex -> Sata cables do not have this 5th wire, can we still use it to plug the drive? What is the use of the 5th wire, is it something important we are missing?

This is a Seagate drive so it does not have the molex connector, only the Sata power connector.

Can we use the 4 pin cable safely?

Thanks in advance.
 

PlasticJesus

Senior member
Mar 16, 2001
412
0
0
I don't know why the fifth wire.

Was the Seagate drive part of the PC already? Seems to me that when I bought my Seagate, it came with that adapter as an extra. This would tell me that it's certainly safe.

I hate that 5 wire scheme. I like to open my PSU up and cut out what I don't use. I actually cut away three of the wires and use the remaining 12v and ground as a cable for my fans. I use one of my other cables and that adapter you're talking about for my Seagate. If I had the knowledge to take that piece apart that you say is broken, then resize and crimp the wire, I might feel differently. It makes more sense when you see my wire management.

4 pin to 15 pin adapters are perfectly safe.
 

Mark R

Diamond Member
Oct 9, 1999
8,513
16
81
The fifth wire is not used by current model drives - these drives currently use 12V (yellow wire) for their motors and 5V (red) for the electronics.

It's intended for future drives which may need a lower voltage for their electronics. I've no idea when we will start to see drives that need this. Until that time the simple 4 wire converters will work fine.

If and when you do get a drive which needs 3.3V it just won't power-up with a 4 pin adaptor.