Recently I had a major problem with an EeePC. After configuration and installation of all the software on it and the optimisation of where all the files go, the machine ran slowly. Checking out the C: partition showed that it had a 30%+ fragmentation figure for the files on the disk, notably because of all the tweaking to get files in the right place. Now this performance issue was slightly counter-intuitive as it had an SSD with no seek times to think of, but file access was horribly slow. This screamed defragmentation (and after I did it, it certainly was down to fragmentation as performance is much nippier now). So the basic defrag tool in the Windows XP Home installation was used but it would not defrag the machine at all even though there was 1.4GB free out of the 4GB SSD. It was simply TOO fragmented.
So I brought in the big guns on this one, which came in the form of IOBIT Smart Defrag. I ran this over the disk and with a small bit of manipulation (moving about 500MB of files to the D: partition), I managed to complete defrag the disk and give the performance improvement I needed. Now you may not have the same level of problem with fragmentation, but I can certainly recommend this software tool over the basic XP and Vista defrag tools, particularly as it gives a lot more visual response for what is going on and how fragmented the disk is, and also it offers a dynamic continuous auto-defrag function (not recommended for SSDs by the way – they have wear issues with file writes that make defrag an emergency tool only) that keeps you optimised.
Great tool, and here is the kicker – it is free.