Is this a widescreen laptop?
With regards to connectivity, there are a lot of things that could intefere with it, do you have a cordless phone nearby? does the connection go off when the phone rings, anything newly installed like a wireless video sender? Is there other networks present in the area?
Also disable UpNp on the D-Link and also gaming mode, whilst this may seem contradictory, it's what was recommended to me by D-Link support staff and it did sort my problems and I've noticed no considerable lag in internet speed or ping times.