Of the several good programs defragment the Hard Drive, Defraggler is one of the most popular, something that has certainly contributed a lot being a part of applications Piriform (CCleaner large developers.) Now comes version 2.0 of Defraggler, important because you look at it even if it's a beta.
Almost a year has made for this update, but this has come up with a very important feature is the scan at startup, which lets you scan your hard drive while the system is booting up and more of the files still crucial for its operation are not blocked.
They have also tweaked the interface and added customization options that allow us to specify our own colors for the defragmentation, but it is especially important to ensure the improvement brought by the new scanning engine, much faster and efficient than the version above.
