Welp, I've made an account here to get some help on why exactly this happened to my DS. Since I haven't gotten the hang of soldering yet, and assumed that I could just play with headphones, I did not solder the speakers to the new screen. I don't know if that has anything to do with my problem but just in case. When I try to turn on the DS with everything in place, the green light comes on, the sound clicks (with headphones) like when it turns on normally, but then the bottom screen flashes once and the whole system shuts down. Is something loose inside (the top screen ribbon perhaps?), do I have to solder the speakers, or do I have to mess with something on the mainboard (I've seen things about F1 and F2 switches somewhere)? (but if i have to deal with that ribbon cable again ugh) Thanks in advance for any help, and I'll provide more info if i have to!