I also have had the same problems with my laptop, an older Dell. I tried the things suggested earlier and then deduced that it was overheating. I spent $25.00 on a dual fan cooling pad which partially solved the problem as well as a small quiet 3 inch fan which really keeps the laptop cool. With that unit, $8.00 at Target, the laptops fan never kicks in to high and sl runs pretty well. Also, performance improved after installing Cool Viewer 1.23.4.