Ok, so you've just installed your Mod Chip, and you've burned your first game, but when you put the game in your PSX, nothing happens, you get to the black PlayStation Screen, but it just hangs.  Now you pretty pissed off, and you are cursing my site, and yourself for trying this stuff out.  But before you toss that coaster you just made in the trash, you decide to take it over to your friends house, and try it out.  As luck would have it, the game works.  So why doesn't it work on your PSX?  Well there are many factors which lead to this problem.  The most common problem is your laser is old.  Yup, years of using your PlayStation can actually damage the laser.   The older PSXs have lasers that ride on a plastic rail.  When the laser moves back and forth over a prolonged period of time, the plastic rail begins to wear, and the laser's lens dips a slight amount.  When the lens dips, the light is not reflected back from the CD correctly.  There are various fixes to this problem, but the most common is to use good media when burning your PSX games.  This means don't use the cheap disks when you burn a game, use good media, with a high reflectivity.  Good disks to use are Verbatim DataLife Plus, and TDK Certified Plus.  I recommend using the one with the printable white labels, I've had the most luck with those.  These CDs are highly reflective, and allow most of the light to bounce back to the lens.  The newer PSXs the Dual Shock ones, don't have this problem, Sony decided to put a metal rail on the inside of the laser.  But for those of us who've been playing the PSX since it first came out, we need to repair our lasers.

So, how do I go about repairing my laser?

Well, the first thing to try is to turn the two knobs located on the lower left side of the PSX motherboard.  The top knob controls the motor speed of the laser (bias), and the bottom controls the intensity (gain).  I recommend that you mark the top of the knob with a pen or marker before you begin, this way you can undo anything that you might have done.  You turn the knobs with a small Phillips head screwdriver.  It depends on you specific PSX problem to decide what knob to try to tun first, and how much to turn it, but a good rule of thumb is to turn only one knob at a time at fist, this way you can get a good feel for the effect.  Also, a small turn might be a huge change, so don't bother to try and spin the knob around too much.  Usually if you have slow load times, and FMV (Full Motion Video) skipping, you need to tweak the top knob, the motor speed.  Else if you are experiencing freezes in game play, or problems trying to use certain kinds of CDR disks, you need to tweak the bottom knob, the laser intensity.

I've played with the laser knobs, but my video is still crappy, and games load slow.   What do I do?

If you've tried everything, and nothing seems to work, you have three last options, buy an new PSX, and put your mod chip in there, buy an new laser, or try to repair the laser your self.  Repairing the laser by hand can is not too hard, but there are places on the web that sell a laser repair kit, that will help you out.  If you decide you want to try and fix it yourself, it will be a lot cheaper.  Basically what you need to do is to take the laser out of your PSX, unscrew the cover, and remove it.  When you get the cover off, you will see a small white gear.  You need to turn it over, and squeeze the bottom of the white gear with a  pair of needle nose pliers.  When you get the gear to pop off, you need to tun it back over, and you will see a long plastic white plate that the gear was attached to.  Slide the plate off, it should snap on and off really easily, or with little force.  Take that off, and you are free to remove the laser.  when you turn the laser over to the bottom, you will notice some silicon grease, and some markings at the back of the laser where the weight is.   These scratches and markings are from wear.  It usually looks like a very slight dip.  What you need to do is to put something in that spot, so that the laser can ride flat on it.  The best thing to do is to take a 3.5" floppy drive, and remove the metal cover from it.    The part of the floppy that is the thinnest is what you need, so you want to cut it out very carefully, making sure you don't bend it.  Then take some super glue, and place it in the worn out spot on the laser.   Then holding the thin metal sliver from the floppy disk with a pair of tweezers, place it on the spot you put the glue on.  Wait for it to dry, and reassemble your laser.  Then try to play your games one you are done.  if you are experiencing trouble, try tweaking the knobs on the motherboard.

Sorry that was confusing, I need to get some pictures, and post them here.  As soon as I do, I'll post them.

Ok, even better, I got this from Michael Mercury:

Laser Repair: