Mate, the 240 is a horrible card, not going to bash it but I guess Intel graphics are more stable than the 240, also your psu is kinda low, if you can check my signature I play csgo at 250 fps without problems, with that being said, try to go to your steam library and click csgo properties, then check cache, this may take a while, if the problem persist try to reinstall, drop a post here after that.The i5 is a really good CPU and 8gigs of ram should help alot.