With blu-ray movies depending on who the company that produced the film is, the movies generally need a different codes. To find a list of most movies, and the codecs they are using, you can check out their movie review at www.highdefdigest.com. Not all movies are listed. For movies that are not listed, using google can generally bring up the correct results.

Another thing that can effect blu-ray, is your card not vamping up because the CPU is not being heavily taxed. This can be fixed by going into the nvidia control panel, selecting the 3D categories setting, and under Global Settings, changing the power management mode to maximum performance.

Also noted, certain media players will lag more than others, try using a different player.