Acer is useless

Most useless company! Can't get a hold of anyone. Can't find a complaints department, probably because people would be complaining all day. I bought an acer aspire 5 core i7 2.8g and lags so much that it takes up to 3 seconds to scroll. I have a 2014 core i3 2.1ghz desktop. It's able to run the exact same programs running at the same time as the laptop. No lag what so ever. Even sent the laptop in for repairs. Got it back with new motherboard and memory. Literally switch it on to a blue screen.