Poor performance on Inspiron 15 7559

So I've been having some serious issues with poor performance on my Inspiron 15 7559.  It's really any one thing, most of my interactions are bad.  When I try to play videos from sites besides YouTube or Netflix I get a very stuttery playback.  It also loads pages slowly as well on chrome and firefox.  I've had Dell reimage the drive with Windows, and have had the motherboard already replaced due to a separate issue with the speaker.  Have anyone else encountered these issues?  After spending $1200 on a laptop I would expect much better performance (at least equal with my 3 year old Alienware, which has an older generation processor yet is super smooth).

ETA: Does Dell have any tech support moderators for their TECH SUPPORT FORUMS?!?  This is the third or fourth issue that has gone completely unresolved when I've posted it to the forums. Absolutely 0 help from Dell.  This is seriously the last Dell I will ever purchase.