I'm posting this on behalf of a friend.
He lives in Brasil and he has 1 MB internet connection. One time he tried to join a server but his download always freezes at 250 KBs and he times out, he tried joining servers containing less download sizes and it worked fine. We tried a set of solutions:
Restarting PC
Turning on single connection
Reinstalling MTA.
Sometimes even his entire internet crashes! please help.