How much of a HDD performance improvement does Disk Defragmenter give?

I was wondering if anyone had recently looked at the performance of defragmenting software? I've use PerfectDisk (PD) for years now on my desktop PC but use the built-in defrag tool that comes with Windows 7 on my laptop. I bought PD in the first place because it seemed to be fast and...

As the title says, it is stuck and has been for the last several weeks. I run the Defragmenter once a week. My system seems to be running fine, so please any help and info about it would be great. I am running Windows 7 Home Premium

How to Use Windows 7 Disk Defragmenter Fragmentation makes your hard disk do extra work that can slow down your computer. Removable storage devices such as USB flash drives can also become fragmented. Disk Defragmenter rearranges fragmented data so your disks and drives can work more...

So I have a Windows 7 Toshiba laptop and I use the default defragmenter to help clean my computer. There are 2 disks that it can defragment: (C: ) and System Beside each of them shows the last time they were last looked at and how fragmented they are. It says that 2% of System is fragmented,...

Hi folks, When I try to run the defrag from the CMD (defrag C: /U) I get an error message that says: The disk defragmenter could not start because you have insufficient priveleges to perfrom this operation. (0x89000024) I have Administrative priveleges. Do I need to switch to a root...