The sync task info is saved locally on your computer. However, the online sync-ed folder is accessible from DriveHQ FileManager or DriveHQ.com website. So if your PC crashes, you can easily recover your files using drag and drop.
If you use DriveHQ service for backup, then please consider using DriveHQ Online Backup. It is more automatic, and is safer than sync. (You could accidentally delete / overwrite a file with FileManager; there is no version history.)