Computers are notoriously fickle creatures. They slow down, sputter and stumble through your favorite sites at will. No matter how new your computer is, it can still be a victim of random slowdowns and crashes.
Usually, these aren't anything to worry about. In most cases, the problem is relatively easy to fix. However, the problem might go deeper than just random, buggy performance. It's possible that your computer woes are the result of a nasty virus.
How can you tell the difference? Here are some of the most common symptoms of computer viruses. If your computer shows one or more of these, you're probably infected.
Pop up ads litter your computer - Running into a pop-up ad while you're surfing used to be a serious problem. However, modern browsers include pop-up protection to keep these annoyances away.
If you're still seeing pop-ups, it could just be a badly-configured browser. However, if pop-ups are coming at you when your browser isn't even open, it's likely you have a virus. This is especially true if the pop-ups advertise some magic cure-all to your "virus woes"
Run a scan with anti-spyware software to double check. I like SpyBot Search & Destroy because it digs deep into your settings to find any problems spyware has left behind.
Messages you didn't send - Most viruses have one goal in mind once they infect your computer: to make the virus as widespread as possible. An easy way to do that is to send messages to as many of your friends as possible in hopes they'll get infected.