As someone that is a T-Mobile customer and someone that is in possession of an Nvidia Tegra 3 based device, it has been extremely frustrating to get the phone to work in it’s full capacity on T-Mobile. First of all, since the HTC One X Global version is designed for PCS (1900MHz) 3G data, most users with this phone will only get Edge.
Now, if you got this phone even more recently and went into a T-Mobile store you would actually get a newer SIM card that is GBA these sims generally carry the version number 50.05. These SIM cards are incompatible with the older version of the HTC One X’s software. In ICS, the HTC One X simply will not get ANY network data with these newer SIM cards. However, if you were able to obtain an older SIM card that is no-GBA and features a version number 50.01, you could at least get Edge and 3G in some areas where T-Mobile has deployed 1900MHz PCS HSPA+.
Now, with the new update, even the new SIM cards are able to connect to T-Mobile’s data network. It appears that HTC has added GBA to the HTC One X with their Jelly bean update and resolved this issue. I was actually preparing to go out and buy one from someone from XDA-Developers.
Now, I can happily get data on my One X and enjoy Jelly Bean and all of the benefits without any issues. Needless to say, HTC’s Jelly Bean update was well worth waiting for.