dell dimension running XP is running slow

[shashgo]

My computer has slowed down appreciably over the last few months.  I have run a virus scan, adware, etc.  using spybot, avira, spyware terminator.  It all comes up clear, no detections.  What else can I do besides maybe defragmenting so I can get it to run faster again.

[Carbon Dudeoxide]

Have a look here:
http://www.computerhope.com/forum/index.php/topic,62253.0.html

[shashgo]

thanks