Hacking Strange problem with a friend's DS phat top screen

[kuroharu]

Hey there,

A friend of mine is having a problem with his good ol' Phat DS. In games with lots of effects or fast paced action, like Sonic Rush Adventure, the top screen (and ONLY the top screen) gets a HUGE slowdown to the framerate, and 3 or 4 horizontal lines appear on the screen. His DS is not modded, and he's using a R4 flashcard. I thought that maybe it could be a problem with the flashcard, so I tried using mine (it's a R4 too), and it had the same problems. He had no problems at all with normal original cartridges.
Any idea of what's the cause of the problem here?

Thanks in advance.

 

[kellyan95]

Sounds like a (very rare) hardware problem. Probably not the screen or connections, I suspect physical damage to a main component. $30 will get you a new mobo on ebay, that may or may not fix it.