Be a bit more specific. Actually, a LOT more specific. If you tell us when, how or anything else which could have led to the random freezing, then it will be way more easier to figure out how to stop it.
Hmm. Can you tell me what exactly happened when the freezing occurred? What happened during and after the freezing? It could help and there is a possibility that it could be a clue to see if whatever happened to me happened to you, too (if you see the thread I started, you can see what I mean).
@maxmahito: Sorry, it was my first thread and I was kind of panicking a bit (and in a rush) when I started writing it. I think I changed the font size to be smaller before you read it. It was so gigantic that I thought even a near-blind person could see it. Well I needed all the help I could get and, hey, near-blind people can help, too. @sinnoh2: Where does your game start to freeze when you start playing Pokemon White? Does it freeze just when it loads up, does it freeze before the menu appears, or does it freeze when you try to play story mode (on the autumn screen)? Also, do you use action replay codes? That can greatly affect if your game freezes before the game actually starts or at the menu. If you do, tell me about it so I can identify if it is a problem with inputting the code or the code itself. I've ran into a bunch of codes myself which cause freezing. I also noticed something about the Acekard. It doesn't freeze like crazy like an R4 or R4i (trust me, I had one before and it was like near shit, almost nothing 100% worked), but it has the tendency to freeze at random if there is a chance that anything, ANYTHING is affecting the flashcard on the outside. If it shifts, even just a LITTLE bit, it will freeze. If A bit of sweat goes on it, it will freeze. If you press on the DS (or DSi, like in my case) a bit harder (even subconsciously), then it will freeze. But normally, what I see in my DSi is that when I go back to the DSi's menu, the game cartridge is not showing, I normally have to take the micro SD out and blow on it and the slot for it, put it back in and then blow on the bottom of the actual flashcard and the slot for the flashcard in the DSi, put them in and then start playing. It doesn't work 100% of the time (maybe 85%) but that's normally solved if I repeat it a few more times. Tell me if any of this could be related to your problem.