alright i have been reading about the ways to power laptops and i have a question i am going to be using a dell inspirion 9300 laptop which does not have a dock (only port replicator from kingston) i believe that this will not provide a power button (damnit) and will not power the laptop (double damnit) so my options are either a carnetix probably the 2140 because according to this link it requires 19.5V (90w power brick) to operate
http://www.notebookforums.com/showthread.php?p=2788159
now the issue lies in that many of the dells have 3 cables +/- and an information wire to talk back saying it is a genuine power cable for a dell. I do not know if mine is the same however if i were to cut it and wire it up to the carnetix would this still work / charge my laptop (posts say that w/o this other cable it will not power the laptop). Then there is the auto / air hookups which seems that it would be much easier except i would not have a way to power the other things such as the screen and usb hub if needed (these would have to be hacked into the cig adapter i am assuming)
so if you could follow this i would appreciate some help before i take the plunge

, i already have a screen and oem hood on the way.
thanks in advance (and i troll here like all day so responses will be quick *clicks refresh*)