My S3 has a black screen and tiny apps on it

[Frustrated S3]

Hi
I have a old Samsung Galaxy S3 that I recently unlocked once I unlocked it I downloaded Pimp my Rom and I think I added some stuff I wasn't suppose to because first my screen became messed up where everything became very small to read I tried going into to fix the screen on my settings and error message pop up saying unfortunately UI has stopped so I did a hard factory resetting which didn't help my screen nor did it clear up the issue with UI stopping once i then rerooted my phone which stop the error messages but now my screen is still the same plus some of the my stuff is starting to go little by little like my home screen is black and even smaller my notifications bar is gone my phone is starting to vibrate and not ring anymore I've cleared the cache tried restarting it in Odin mode can someone tell me what's wrong with my phone like did I fry it and whether it can be fixed and how please another thing that just happen my internet just shut down now while typing this so I have to use wifi please help me thanks

 

[Rukbat]

It sounds as if you changed the screen resolution to something useless. Reflash the stock ROM using Odin (you should be able to find the stock ROM on SamMobile Firmwares ) and the phone should work again. (Make sure it's the ROM for your model/carrier/country S3. Flashing the wrong ROM could brick the phone.)

In the future, make sure all your data is backed up, play all you want, but don't change the screen resolution until you read about it and understand what changing it does. (Making it too small to read means that you can't get back to PMR and change it back.)