8gb memory stick issues

I recently bought an 8gb memory stick off amazon. the psp shows it as 8gb so its not like it only reads 4gb or something like that. i put 3 iso's on it and only 2 showed up. and i know for the fact the 3rd one is NOT a bad dump because i was running it before on my 1gb stick. im running 3.90m33-3 but can update to 5.02Gen-A. Also, whenever i try to save the game with one of the 2 iso's that does work, it shows up with an unholy amount of corrupted data. this can be anywhere from saying 60gb-317gb... any solutions?

Do What I Did

1)Format the stick from your computer
2)Copy all the files from ur other mem stick.

o my gosh, now i put mgs on there and it runs fine, save works well. i put god of war on there as well, and it DOESENT EVEN SHOW UP UNDER GAMES! i'll try some others, then edit this post with results

EDIT 1: got gpsp working. transfered a bit of save data as well. maybe 3 gigs worth of iso's just overloads it

Are you copying the game under the right directory?

PSP ISO games go into the ISO folder on the base of the stick.

could it be a fake stick?

could it be a fake stick?

That's what i'm worried about. However, if it was a fake stick, why would it be able to have one iso on it? gpsp works but i can't add files to it, i have to recopy the whole thing