The first one, I always save. When I first install an OS, the first things I do is defrag, then backup. That way, I have a clean starting point, as C_C already pointed out. I usually keep three, the second being the one after all of the usual software is installed.
Then, after a major program is added, or a huge round of updates like yesterday, I make another one. After that, when I make another one, I delete the last. If I didn't, my backup drives would be packed full.
A single backup of my computer is nearly 600GB, so I now do it at bedtime, Acronis can be set to shut down the computer when it's finished. The last time I done it during the day, it took almost two hours. I've added a couple of VM's since then, so I just set the backup on auto pilot and hit the sack.
A 2.0 USB connection is not the fastest way to backup, but it's better than nothing.
Cat
