Hmm, two R4i 3ds (clone) cards, and one M3 Revolution (probably also a clone) card for my DS Lite. wonder if any of them work.
The M3 is dead, definitely. (also it's an M3 DS Simply). it won't read the micro sd card at all and the spring catch inside the slot for the micro sd (WHY does it have that seriously ugh what a bad design) is broken so the sd card woon't stay in no matter what. I don't have a small enough screwdriver to take it apart either.
As for the R4 Rev, (also def a clone) it also doesn't read the card and I think it might also have had a spring catch because the sd card sits... very low in its slot... The DS lite just doesn't read the M3 or R4 as existing, and the R4i 3ds's firmware on the sd card is apparently fucked I guess. Shame. Ah well.
Not sure what caused this because the R4i was definitely working, I was playing Cooking Mama 3 on my DS lite. Then suddenly just... whomp. White screen forever. :<
The R4i 3DS just white screens on booting up so... I have no idea what's up with THAT one. yow.
the otyher one I have is actually an R4 Revolution for DS. not another R4i 3ds, forgot I sold that one (mercifully it worked).