my requirement is

1) it should backup the serverDB with timestamp.

2)**** It should not append to the existing backup file .bak, it should create new backup file to the given drive.

3) it should be easy to automate the process daily.

I've just tried one sql server backup software named Easeus Todo Backup which is famous for its free edition. i think its advanced Server edition which is designed for Exchange and SQL Server database backup can meet your demand.

1) it's backup file is named after the backup time, or you can name the backup file yourself, and you can also add description to the backup file then you will easily identify each different backup file.

2) it creates new backup file of individual or whole database and saves backup file to local hard drive or tape.

3) you can set backup schedule to do automatic database backup. It supports daily, weekly and monthly backup.

you can download its free trial to try it out at http://www.backup-sql-server.com/download.htm