Acer laptop won’t start after recent upgrade

Hi, I've been using an Acer Travelmate P243 with a 2GB RAM. I have recently upgraded the RAM using Corsair Vengeance 8GB DDR3 1600 SODIMM which I bought from the local store. I followed a Wikihow step-by-step procedure on changing the RAM.
Right after the upgrade, I turned the unit on to check on the success of the RAM replacement. The display screen shows blue screen only. Help!?
