Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a Dell Inspiron XPS 15 (L502X) laptop, with an eSATAp port. I also have a Western Digital 1TB 3"5 SATA drive, that I'd like to use with the laptop.

I bought a eSATAp <-> SATA 22-pin cable (from Delock).

When I use this cable my 3"5 HDD does NOT power up, no spin up.

I thought that it's just this HDD taking too much power from the motherboard. However, I tested too with my 2"5 SATA HDD and it works successfully.

Now the weird thing is that this 2"5 HDD takes 1.1A at 5V, and that the 3"5 HDD takes 0.7A at 5V. I don't understand why it can't work.

Is there anything I could do for it to work ? What is really the problem ?

Thanks for your help,


share|improve this question
I know found out what's not working : the 3"5 does not only take 0.7A, in fact it uses 5V and 12V at the same time. My question is now : using another cable is there any way for me to provide power to the HDD from the laptop ? – pistache Mar 19 '12 at 19:54
up vote 1 down vote accepted

There exist two versions of this port. The first one, usually built in laptops, provides only +5 V through the USB connection. The other one has additional two pads, placed against the plug's "horns", which provide +12 V. The second one is needed if a 3.5" HDD or 5.25" optical drive is plugged into an eSATAp port. Cables are built with or without +12 V support. This leads to user confusion as they are usually unaware of the details of +12 V power delivery. So look for these on your laptop. Or buy an adapter

share|improve this answer
You are right, this is what blocked me. In the meantime I found that adapter. Thank you. – pistache Oct 17 '12 at 10:58

You need to get an external drive enclosure with a proper power supply. 3.5" drives aren't meant to pull power from the 22 pin connector.

share|improve this answer
Thanks for your answer. I managed to power the hard disk drive using and old USB 2.0 enclosure with power supply. – pistache Mar 20 '12 at 19:22

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .