IC = the name electrical engineers used to use as a "posh" name for chips on a circuit board back in the 80s and 90s, and anyone using it today is just trying to pretend like they know more than you.
It's worth trying taking it back to the shop. They may offer a replacement free of charge if you have proof of purchase. On the other hand they may want to send it away. Just depends on the shop.
"Totally Agree best deal by a new device,fix and old device never the same" isn't hard to figure out. He's saying he totally agrees with you, you'll get the best deal if you buy a new device. Getting the old device fixed isn't the same as getting a new device (because new device = faster, better, newer OS, etc).