I purchased a great lakes chip from navionics and then sent in a card that came with it for a second great lakes chip to be used in conjunction with the first chip. I am thinking I need to load both chips, right ? If so how do I do it ? Or if not so then how do I use the second chip ?

I Don't know what kind of unit you have but my X38 HD has 2 slots I can put chips in and I just tell the unit which one to i want to use.

I have the lcx-19 with 2 slots also, but don't know how to load the second chip

I think you can only load 1 Chip map at a time. Think it's like a different lake you change to.

Rebs,

Not sure what your trying to do but you only can view or need 1 chip at a time in any unit. You can not overlay different maps and view one on top the other. If you have 2 different brands of mapping chips of the same area you can put one in each drawer of an x19 and toggle back and forth to the one you want to view via the map data menu.

You could insert both of your identical (if I understand correctly) chips in your X19 also one in each drawer but there would be no reason to do it.

However if you have a second gps on the bow of the boat the second identical chip can go in that unit and then you will be looking at the same map in both locations of the boat.
keep in mind the information on these chips is not "loaded" onto your unit permanetly.
It only replaces the factory Lowrance map of the area you are viewing while the chip is in the drawer and you have properly selected to view that chip through the "map data" menu choices. When you open that drawer and remove the chip the new map goes away and you go back to the Lowrance factory map.

Make sense?