How Full Is "Too Full" On a Hard Drive?Although you can pack a hard drive right up to its rated capacity, it is usually a bad idea. Among other things, it is likely to make the system perform poorly or crash unexpectedly. One reason is that many programs create additional, temporary files when they run. Sometimes, as in the case of a spreadsheet or database, these files can be extremely large. Although these files might be temporary, if the program can't create them due to lack of space, it is likely to crash, potentially your data at risk. Another reason is that it is very difficult to efficiently defragment a hard drive or partition that is more than 80 percent full. So how full is "too full" on a drive or a partition? A good rule of thumb is that anything over 80 percent of capacity is too full. At that point you should move some of the material to another disk (or partition if it is a partition which is filling up), even if it means adding another hard disk. If you can't add another hard disk you should consider alternatives. If a partition is filling up and there is more space on the drive, you might want to enlarge the partition using a tool such as Acronis Disk Director Suite. Other alternatives include using a compression program to compress some of the files or transferring some material to removable media such as a Zip drive or a writeable CD-ROM.
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Acronis Inc. Backup software.