vu sur le site ign :
Game Boy Advance Too Dark?
The IGNBoards are all a-buzz about an amazing discovery: the Game Boy Advance's contrast control.
A discovery has been made, and it's set the IGN Message Boards ablaze with folks excited about a "new" feature of the Game Boy Advance.
Apparently, the Game Boy Advance has, hidden away, a contrast adjustment potentiometer that can be turned to brighten or darken the Game Boy Advance's LCD screen. The Game Boy Color and NeoGeo Pocket Color systems also had this feature, and it was just as well hidden as the GBA's.
What you'll need is a small screwdriver, as well as the will to void your warranty -- because once you've revealed the location of the contrast controls, that's what most likely will happen.
Warning -- I hold no responsibility for what happens to your system if you proceed with this. My advice...leave it alone. Don't touch it. Really.
Okay...here's what you do: Gently push the tip of the screwdriver against the right side of the silver Game Boy Advance label on the back of the system. Watch the sticker -- you'll notice the label push inward and reveal a circle. This is the hole where the potentiometer is in. You'll have to pierce the label with the screwdriver to reveal the hole. At the bottom of the hole is what you need to turn with caution with the tiny screwdriver. Watch the screen as it slightly dims and darkens as you turn the potentiometer (or pot for short).
Keep in mind that the actual potentiometer is hidden for a reason -- it's not made for users. It's only meant for authorized Nintendo repair technicians to utilize, just in case your GBA system needs specific adjustments. And this adjustment will not eliminate the need for an external light source. That's just silly.
-->source : http://pocket.ign.com/news/35946.html
Avis à ceux qui ont une GBA : ca marche ce systeme ?