The boat i am buying does not have a tach or speedo and i would just

prefer to drill in the hull for one transducer.How accurate are the

depthfinders like a x96 with the temp,paddlewheel speed unit together?

I know a tach can simply be plugged into the yammie engine and a

gauge bought. :-/

If you want reliable speedo get a unit with GPS.

I have a humminbird Matrix 87c (newer model 787c) that has one transduser. the transduer has temp on it. the speed is from the GPS  in the unit. I have speedo on the boat. It has been broken since I bought it. fixed once, lasted about 4 trips. I know very few people whos speedo in the dash works right. everyone uses GPS for speed readings

First, the speed has to be calibrated with a GPS. Right out of the box, it can be bunches off. I have a Lowrance with speed and temp on my Stratos and once I calibrated the speed with my gps it was very accurate everytime I spot checked it against the gps, much more so than the speedo. I like it not so much for the speed but for the odometer. I think you will also find as mentioned, the Temp is in the Xducer, the paddle wheel is only for speed.

Forgot,the paddle wheel,temp unit is not with the transducer for depth right?

I would still have to mount two units to the boat? :-?

If you only mount the transducer, it should give you depth and temp.  You have to mount the paddle for speed/odometer.

Yes, to get Temp, Depth and Speed, you have to mount both units.

To only get depth and temp, you only have to mount the transducer