Sunday, July 31, 2005

DVD Blowout

Sorry for the gap in entries -- Uncle Mark had a few things to do. But, we are back.

As I mentioned in an earlier post, we moved to a new house. Moving takes a lot of time, and I hadn't the chance to work with our computer much. When I finally got back to the computer, I noticed that the DVD/CD drive was stuck -- would not open. I messed about with it and finally got it open -- the CD that was in it was jammed, and I managed to keep it from getting in the way of the door when it opened.

When it did open, I saw something I had never seen before - a completely shattered CD. The drive was full of fragments and shards of CD. I suspected a few things - someone had put the CD in the drive incorrectly, and it shattered when it was closed, or that my boy had gotten into it somehow. However, neither made sense. I don't know if you have ever tried to break a CD or not, but it is not an easy task. One way is to just fold it in half (no doubt you should be wearing eye protection) until it snaps. You will get either a very bent CD, or if it snaps, two halves and some shards. You do not get the whole CD in shards, which is what was in my DVD drive.

Being a professional, I tried to see if I could fix it. I have a Gateway, relatively recent model, so it is built to be easy to service. I turned it completely off, and unplugged it. I popped the side off, and unscrewed the screw holding the DVD drive in its bay -- one screw, and the screw has ridges on it so you can unscrew it with your fingers.

Drives in PCs have, usually, two cables going to them: A power cable, and a wide, flat data cable. Both cables connectors are set up so that you can't put them on backward, which is nice. I just pulled them off before I slid the drive out of the bay. The power cable is usually a bit difficult to pull off, but it is rugged, so you can just yank away. By the way, this is why you unplug the computer -- you do not want to be zapped when working on your computer. Oh, you'll probably recover, but your computer can easily get fried.

Sliding out the drive, I heard a very ominous sound. What you are supposed to hear when you turn a drive over is nothing. What I heard was what you would hear if you had a bag of broken glass and rolled it around. When I slid out the tray and shook the drive, chunks of CD of varying sizes fell out.

I knew that the drive was probably a goner. Usually, in this circumstance, you would chuck it and get another. However, with nothing to lose, I elected to open the drive to see if I could clean it out and get it working again.

This is something that you really shouldn't do -- you can maybe get away with it with a DVD or CD drive, since they are relatively open, but you can not do this with a hard drive, and expect it to work again. Hard drives are hermetically sealed and need to be worked on in a "clean room" (not your mom's living room, but a lab with filtered air) by very patient people wearing paper suits who have the right equipment. But a DVD drive that is already busted -- there is a slight chance of success.

I opened it up, and there was shards all over the place, and CD "dust". These are shards so small that they are like diamond dust. I did what I could to take out the pieces and clean out the dust, and then I put it back together, and put it in the computer.

Alas, it didn't work. It was better, but computers are binary -- either they work, or they don't, and the DVD drive didn't.

So, yesterday, I decided to buy a replacement. We are up in the North Bay of CA, and there is a computer and electronics supply shop nearby. I could have gone to the chains, maybe Best Buy or Fry's, but I like to shop local.

I found a DVD drive for $30. I expected more like $70 or $80, but here it was for $30 -- and not some off brand, either, but LG, which is a respectable manufacturer.

I took it home, and installed it. Took ten minutes, and almost zero configuration. However, a bit of warning is in order:

When replacing a part in your computer - should you want to attempt this - it is important to exactly duplicate the settings of what it is you are replacing. There are these things called "jumpers" that configure selections on hardware like drives, motherboards, video cards, etc. In this case, there is a jumper on DVD drives that gives you three choices: "Master," "Slave," or "Cable Select." The DVD I bought had this set to "Slave." The DVD that was broken had it set to "Cable Select." What is this? Well, you can Google it, and there is a ton of info on this, but suffice it to say that is a technical hardware setting about how the drive is to be treated by the computer's communications system. What should it be set to? That is easy -- make it the same as what you are replacing. In this case, the one I was replacing was set to "Cable Select," so I moved the jumper (a very tiny little connector that "jumps" between two posts) to the setting for "Cable Select." I put the computer back together, plugged it in, turned it on, and it worked! It played a DVD movie, and played a CD.

So, how did the CD shatter in the first place? Well, a bit of research led me to the conclusion that the CD that shattered was a bit defective -- physical flaws. The drive is (was) capable of spinning CDs at 40-50 times normal speed. Basically, the drive was spinning the CD so fast that it blew up! I did not know this could happen -- but it can!

All is well now, though. I guess the moral of this story is, treat your CDs with care!