Overburning a CD is the process of burning more data to a disc than the specified capacity it is deisgned to hold. For example, if the data-holding capacity of a CD-ROM is 700 MB, by overburning it you will end up with more than 700 MB of files. This technology is very useful as there is no need to split and burn data across several disks. Most of the latest hardware in CD and DVD writers support this Overburn feature. However, if your Nero software is older than Nero version 6, the overburn feature is not enabled by default for the CD/DVD drives to support overburning. In case you need the writer to store more data, you have to enable the Overburn feature from the settings in Nero before burning the disc.
The Overburn option is used when you want to burn data or image files larger than the disc capacity than the CD/CD-RW would allow you to write.
This method is more suitable than splitting and burning across several discs. Nowadays, most new CD/DVD writers support this feature.
You can Overburn your discs only if you have Nero 6 or later.
Setting up OverBurn option
Click on Menu
File > Click on Preferences
Click on the "Expert Features" tab
Check the "Enable overburn disc-at-once"
Now set "Maximum CD Length" to 99 min 59 sec 74 frm (850 MB CD)
Please note that if you want to OverBurn a disc of 800 MB, set the Maximum CD length to 82:59:59
Please note that this process has caused some writers to become unreadable.