I would use Robocopy, this way you can back up what you want, and it'll only back up the files which changes.
Syntax
robocopy \\<Source> \\<Destination> EG
Open Notepad, and type in (using correct folder names)
robocopy \\SourceServer\Share \\DestinationServer\My new folder\BackUps and save it as BackUp.bat (note the .bat)
Then, set this file to run via TaskScheduler (in your Control Panel) as often as you want.
Further, there is an option to do File Syncronization - http://improve.dk/simple-file-synchronization-using-robocopy/
robocopy \\SourceServer\Share \\DestinationServer\Share /MIR /FFT /Z /XA:H /W:5 Parameters you may be interested in (from link cited above)
/MIR specifies that robocopy should mirror the source directory and the destination directory. Beware that this may delete files at the destination. /FFT uses fat file timing instead of NTFS. This means the granularity is a bit less precise. For across-network share operations this seems to be much more reliable - just don’t rely on the file timings to be completely precise to the second. /Z ensures robocopy can resume the transfer of a large file in mid-file instead of restarting. /XA:H makes robocopy ignore hidden files, usually these will be system files that we’re not interested in. /W:5 reduces the wait time between failures to 5 seconds instead of the 30 second default.