Winch Power

I have a Smittybilt XRC8 winch and have noticed that my lights dim in the cabin when I am using it. Now I come from a car audio world, and know that this means it isn't getting its required power to operate properly. I have just recently bought a P5 Group 35 Diehard Platinum battery and still have this issue. I do plan on buying another one to run a dual battery set up with my columbia overland kit. What I am wondering, is, does anyone else notice this in their trucks as well? If so, what have you done to feed enough juice to your winch? I have the OEM tow package Off Rd 4x4, so I have the larger alt....

Oh yeah, MERRY CHRISMAS!

 

I turn everything off that I can. If at night, I turn off as much light as possible also. Winch away!