"How to speed up a computer" is like "what should I do when my kid's sick?" What's the computer? What do you use it for? What do you not use it for? What OS? What hardware, software, etc.??? Tell us all about your computer. Then tell us what it's doing or not doing that causes you to ask the question. Then we can give you advice. Example: Dell model blah blah blah running WinXP SP2 and it's a dedicated trading box. I don't go online with it; it just gets a datafeed for charts & a trading window. Suddenly charts are lagging or freezing - what do I do?
Thank you for all those advices. I'll keep them all on my armory of computer first aid tools. Thank you for the advices guys. They've been a great help