Hi, I bough a Galaxy S3 on Ebay it says GT-I9300 but it has 2 GB ram and Dual Core so I don't think it's really I9300, but when I connect to kies it identify as GT-I9300, but when I go to Download mode it shows me Model Name: SGH-I747 and custom, I tried to root many times but I bricked my phone, and with good luck I fix my phone, I just want to know which is my version of Galaxy S3, and I just want to upgrade my Android version from 4.1.1 to another better but stock rom only, without brick my phone (again). Thanks a lot