Need advice on a good fish finder/ chartplotter

[cacoon]

I too have a question about fish finder's. My boat came set up with a Lowrance x37 fishfinder. I know its the very basic of fish finders. It is 6 years old. It would not power up this last trip. I haven't checked the fuse yet. If it is the fishfinder finally crapping out, if I buy a new one can I just hook it up to the existing wires and use the set up that is already there. Or completely remove the whole old system and replace with all new stuff not just the fishfinder itself.
Thanks Cacoon
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