Кстати, надо вот попробовать:
Random freezes and stutters in Skyrim: If you are getting random freezing or stutters, it could be your Anti Virus program. Some anti virus programs constantly scan files which are being used, and this could cause your game to stutter and freeze at times. If your anti virus has a Game Mode, it is highly recommended to use it while playing. Turning off your anti virus program is not recommended. Although, finding an anti virus program which is more lightweight is. Some anti virus programs are very bulky, and cause games to have low FPS.
У меня кроме антивиря еще пара резидентных прог висит проверяющих в реал-тайме запущенное и вызываемое файло. Попробую отключить, вдруг поможет.