If speeding up your PC is on top on your To-Do list, it's best to diagnose the problem first. So, before asking "How do I speed up my PC", ask "Why is my computer running slowly?". The most common causes of a crawling PC are spyware and viruses, too many files and applications, depleted disk space, outdated hardware, and low memory. Anti-virus protection is a MUST for your computer, so if you don