Alienware M17x R3 (Early 2011) USB eSATA

Hi,

I bought already 2 different cables for my external eSATA port to have an external 3,5" Hard drive for my personal files on my laptop. So far only small 2,5" Hard drive work with the cables but my 3,5" Hard drive will not even start to spin. 
I researched It before and I believe it the port should support 12V for the big 3,5" Hard drive.

Do I have to turn something on / off in the BIOS?

Do I have to upgrade some drivers?

Does someone get a 3,5" Hard drive get to work on his M17X ??

Is my laptop to old to support the 12V?

I really need this to get work because I have to much personal files what I need on my laptop and I would have them secure on a external Hard drive.

Thanks for the help

Dave