Quote: Originally Posted by
vrslider 
how thick must the ground cable be ? I want to use a 6 mm wire is that enough?
The ground cable should be at least as thick as the power (constant +12v) cable.
Here is a handy dandy chart:
http://www.powerstream.com/Wire_Size.htm
And those size diameters are for the copper itself, not copper and insolation. FOr instance I have 4awg wire which is about 5mm thick on the copper side, and about 1cm thick total.
For the M2, 10awg to 8awg is the standard size. Thicker is always better. I used a bigger cable because I like the option of upgrading. One day I might want a DS-ATX, so instead of having to switch out the power supply and rerun a thicker cable, I just will have to switch the ps and be done with it.
And in case you havent picked it up yet, the lower the number for awg, the thicker the cable.
4awg is thicker than 8awg which is thicker than 20awg.
And make sure you are running your power cable to the battery. If you dont you
will be sorry.