To speed up the hard disk speed we need to set up a special buffer in computer memory to enable it to better address interruptions from the disc. This tip is only recommended if you have 256 MB of RAM or higher.
Follow this steps :
1. Run SYSEDIT.EXE from the Run command.
2. Expand the system.ini file window.
3. Scroll down almost to the end of the file till you find a line called [386enh].
4. Press Enter to make one blank line, and in that line type Irq14=4096
Note: This line IS CASE SENSITIVE. Click on the File menu, then choose Save. Close SYSEDIT and reboot your computer. Done. Speed improvement will be noticed after the computer reboots.
Source : http://dhuwuh.blogspot.com/2008/11/increasing-speed-of-hard-disk.html