I have a Lenovo y510p laptop (750m sli) with windows 8.1 operation system and 8gb ram. (vbios updated). Maybe a year ago -when I had windows 7- it started to freeze (black screen) when I play games with SLI and I had to manual restart the computer. Now I have windows 8.1 operation system but the problem is the same, only the game stops with error message and the realtek driver says that "A jack has been plugged in" (??). I also have a problem with the sound system. Sometimes the left speaker is quieter then the right one and if I increase the volume to maximum then back, it works well again. (windows 7, 8, ubuntu) I have 170W adapter so it can't cause the problem. Yesterday I update the system bios from 3.05 to 3.08 and the the sli problem is nearly gone. The game sometimes start fps drop (and I hear the gpu fan go down) but it isn't crash or freeze. The sound problem has not appeard since. I wanted to bring back it to the lenovo service but I don't know what to do now. Does anybody have a changelog for the system bios update since 3.05?