Some times even off the factory line a optical drive can be a little bit dodgy when it comes to reading certain types of media. In this case the Xbox 360's dvd drive becomes weak over time and you get the dreaded "dirty disk" "open Tray" or "unreadable disk" error. This error can even occur on new boxes that the drive just needs a small tweak to get the dvd laser diode potentiometer to its sweet spot. All drives are different and no 2 drives will have the same base resistance on the dvd "pot". Its common for most drives to be factory set any where between 4Kohm-6.4Kohm and in this guide it is highly recommended not to lower the resistance to your DVD laser diode below 3.2Kohm, this is the lowest resistance that is safe before you risk blowing the diode out in a very very short period of time. So what we are doing by decreasing the resistance of current flow to the laser diode, is basically increasing the lasers power. thus making it easier for the laser beam created by the diode to be focused by the laser lens and be reflected back so it can be read by the assemblies optical sensor. WARNING: -NEVER EVER EVER attempt this with out a multimeter to measure your adjustments. Remember the purpose of this tweak is to extend the usable life span of your DVD-ROM, not gambling blowing the laser diode in the first 15 min of using a DVD-ROM disk in it. So why bother gambling it? it would defeat the purpose of this tweak. - ALL "Pot" adjustments will be very small, moving it a hair can make a difference in .2-.5Kohm in some cases, so use small adjustments and then read the resistance with a multimeter - Do NOT EVER lower the resistance to your laser diode if your not having disk read issues -REMEMBER this is not a tweak that will fix your issues with Game/Movie Disks that you abused and have scratched beyond readable use by the drive. Although it may help with minor scuffed disks, if you have trashed the DVD-ROM then its garbage. no pot tweaking or any other song and dance besides replacement or resurfacing will fix that it. -------------------------------------------------------------------------------- - Take note to what way I instruct to turn the pot to decrease the resistance value of the pot. it differs between Lite-On/Ben-Q and Hitachi/Samsung -Measure resistance with a multimeter between the two spots i have marked in red. Set the multimeter to 20Kohm. ALSO the pot on the right is for DVD Movies not games Here is what you are looking for: I DO NOT TAKE ANY RESPONSIBILITY FOR ANY DAMAGE DONE. THIS TUT IS FOR INFORMATIONAL PURPOSE ONLY: Please +rep if this helps you.