As an automatic melee weapon, it attacks similarly to other chainsaws. The chainsaw found in Appalachia is a Romington-brand Super 76. The chainsaw is listed as a weapon only, making it incompatible with any melee weapon buffs or perks. The damage will not scale with Strength.
Clarksburg - On the top floor of the hardware store, on a shelf above a safe.
Crimson Prospect - Can appear southwest next to a bus, on a metal shelf, on the bottom row.
Mountainside Bed & Breakfast - Can spawn in the basement on the shelf with the ammo box. As of Wastelanders, one can become permanently locked out of the basement (and thus this chainsaw) by completing the miscellaneous quest with the cannibals.
Poseidon Energy Plant WV-06 - Inside the South Expansion, on a table with a portable grill, on the upper level accessed through the broken pipes.