couldnt backup database

Hello all, I've a table in my database with 1 lakh records using a disk space of around 50Mb. I wanted to download the records. I used phpmyadmin (coz my hosting provider doesnt allow remote access to my db) to export the database but its not working for larger databases. I thought that it might be a problem with the max execution time. So i thought i wud manually store the records in a text file so that i can download it. But when i tried that its not creating the file beyond 10Mb. I've tried these things out.. ini_set ( max_execution_time, "300"); ini_set ( mssql.connect_timeout, "300"); ini_set ( memory_limit, "5000000"); but not working.... can anyone help me out with this problem.. Thanks, /sagar