At the very least, a faster CPU would kill your battery life if it does fit. If the existing chip is a 'mobile' CPU, it will show improved power saving capabilities compared to 'standard' P3, P4, or Celery models and run at lower temperatures.
Try to check your laptop maker's website for specs on the mainboard, see what type of CPU it is designed to take.
If this is a desktop, upgrading a Compaq is rather pointless, the mainboards are often set up to handle a limitted range of options. You might cram a 500 or 650 in there, good luck on adding a 1300. One upgrade that might actually do some good is to add more RAM to the usually minimal factory allocation.
Edited by MalikTous, 01 June 2005 - 02:36 PM.