Windows 8 users though may not opt for third party....

http://blogs.msdn.com/b/b8/archive/2012/07/10/protecting-user-files-with-file-history.aspx

I just built a DAW a couple weeks ago. The SSD came with Norton's Ghost so I'm using that and an external HD for backups. I did the first backup after updating Win 7 and all the drivers for the base system and another one after installing the SW I use most often - Sonar X2, Omnisphere, VG-99/GR 55 drivers, etc. I still have some SW to load - drivers for older equipment like an Aaki Z8 that will probably require XP mode and I'll do another backup after all that is loaded.

I use Acronis 2011 and have done a successful restore of my C drive on my DAW.
I have a rotation of three backups to an external drive of all three of my drives.

I also use SyncToy on my projects folder to an external drive just to be "extra" safe.

Seems like all backup software gets bashed in user reviews. I installed Acronis 2013 recently and so far so good. I've restored a deleted file successfully with it. In the past I've used the free version of Macrium Reflect to restore a drive image to a new hard disk.

+1 for Acronis, I use Acronis True Image 2011 and it works great. The only thing you have to remember is to NOT set it up to do constant realtime backups. That's going to hit your DAW's performance. The backup plan I've settled upon is to have it do an incremental backup of my system folder and data folder once a day, upon shutdown. It means that you have to be careful when you shutdown - if it's gone past midnight and you shut down, the shutdown is going to take a long time so I have to remember not to restart my computer unless I know it's already done the backup that day. In emergencies you can disable it so that you can do a quick restart though. 

Lots of other handy disc functionality comes with Acronis. You can make recovery boot discs for example, and also you can do a reformat with high security data wiping algorithms.

There are several strategy for backup: 1) physical disk copy ( Clonezilla or other Linux solutions) Pro.: does not depend on what is copied, so complete independence from the OS(es) on the disk (no OS compatibilities issues by definition). Also it does not depend from the backup software at all (can be restored using any Linux, probably in 30 years as well ;), restoring particular files requires Linux skills Cons.: the backup size is ALWAYS the size of the disk (so, it is slow and takes a lot of space), requires reboot for backup (can not be used from Windows). 2) disk/partition copy with unused blocks suppression (all mentioned programs) Pro.: in case of Clonezella, does not depend on particular Windows version (while see cons), the backup size is equal to the used part of the disk Cons.: depends on the file system, so there can be some Windows dependent issues (while sine Win Vista time I have not seen any), depending on software, it can be impossible to restore separate files, quite slow operation. 3) file system incremental backup (Acronis, Ghost) Pro.: writes all changed in separate files, so is normally fast, separate files can be restored Cons.: Windows version dependent, each software does that very proprietary way, if some backup in a chain is broken the restore can be problematic (for that, the software makes periodic complete backup) 4) file based backup (mentioned Windows 8 way, some other can do that as well) Pro.: only required file are saved, so only small backup space is required, any version of any file can be restored Cons.: it is impossible to restore complete working system, very OS specific When I want to be sure "I have it", I use (1) For situation when I am ready to loose one day of changes (at home) I use either (2) or (3) For "production" environment I use (3) + all files on RAID 1/5 (well... really I use RAID10 on 20 disks, but that is not for music ;)

I've used Acronis since, I think, Acronis 2009, I'm currently running 2013.

It seems to backup ok, but I haven't had cause to restore anything yet.

If it doesn't work when I do, Acronis will be faced with a rather large bill.

Oh yes, I also copy my Projects drive onto another external just using normal Windows Copy & Paste.

These are rotated on a schedule but I have another called "Archived" which never gets deleted.
This contains all my stuff from Sonar 6, 8 & 8.5

I tried Acronis a couple of years ago. Although the product had great integration with Windows, it was a bit of a bear. Although it had many options, the system didn't seem to have a very well-thought out menu system. Also my impression was that the thing was interfering with Windows performance. It's been a while, so maybe things have improved since then.

I use Retrospect Professional for Windows. It can backup your your entire system, do differential backups. Options are available for servers, tape libraries, and such. It's a top notch product, very easy to use, easy to setup schedules, and lets you backup remote computers as well (do the whole house!)

..two cents..

Seems to me after reading all this that upgrading to Windows 8 is a good way to get half decent backup software (bundled), although I haven't used it yet (see prev link I posted).