4GB is not a whole lot when it comes to games, that may be your problem right there. I don't know how to fix this if it is too little since we're talking about a laptop that probably isn't designed around gaming. Laptop designers typically make it hard to replace parts, if not impossible, on purpose to get people to replace the whole thing when hardware starts failing.i'm not of pc gamer so bear with me.
well i'm on performance mode and my laptop is a lanovo with an intel core i3 and it's got 4.00 GB.
does that help?