I don't think ram is going to cause the issue you are having. Ram either works, or it doesn't. If RAM is bad, you get all kinds of red screen and random reboots. Doesn't cause hiccups like your machine. I would be more inclined into looking at what topgun suggested. What os version do you have? You can get it by turning jackpot reset key and hitting version-packages-system. Post a screen shot of that and we can figure out what OS you have. I'm leaning toward the solution posted earlier.