1995 Chevy Lumina Loud shrieking trying to start Van

Let me start by describing the growing problem I've been having with my Lumina Van, with the 3.1L engine. Ever since we installed a replacemnt A/C compressor, we noticed a louder than normal shreak or squeal. (To me it sounds like the engine belt has to work too hard to turn this component)
I've had to apply belt dressing, which doesn't seem to work anymore.
Lately, its squeals very loudly when turning over, then disappears.
Today, nothing. Plenty of charge on the battery, but it sounds like the starter has too much resistance.
When I finally got it close to turning over, I heard this unearthly squeal. I shut down everything and saw smoke rising from the engine, the burnt rubber smell, and a fine layer of gray dust exactly under the serpentine belt. Has something seized on the serpentine belt?

Please tell me its not timing belt related.
Thanks for any advice.