New belt squealing, smoking

97 Dodge Intrepid, 95000, 3.5L V6 - Hello. I am new to car repair, so please bare with me. We just recently bought a 97 Dodge Intrepid for a too good to be true price. The only thing that was supposed to be wrong with it was that it had no AC belt (V-belt that runs the compressor). I have no idea how long the car has been without an AC belt. Wanting to save money by doing whatever I can myself, I replaced it. Removed the serpentine, replaced the v-belt and replaced the serpentine belt. Now when I start the car with the AC running, the car will run quietly for a bit and then the belt will start to shriek. The first time I started it, the belt smoked a lot and squealed. Second time just squealed but I didn't run it as long to see if it would smoke again. The smoke seemed to be coming from the area of the tensioner or the pulley above that. All pulleys seemed to be turning, but I couldn't see the tensioner. Any ideas? The Autozone guy said I shouldn't need belt dressing for a new belt.