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So You Think You Have a Virus...

I commonly hear folks say, "My computer is SO slow.  I must have a VIRUS."  I can't give an accurate percentage, but MOST of the time this simply is not true.  Here are some of the most common reasons for a slow computer (in no particular order).
  1. Computer is running too hot.  This could be due to poor ventilation and high temperatures around your computer and/or dirty fans and heat sinks inside your computer.
  2. Hard drive free space is too small or data on drives is heavily fragmented (especially system files and the registry).
  3. Too many processes are running.  Windows XP out of the box runs about 30 processes.  Install a printer and its software, an instant messaging client, a caller ID app, turn on fax service,  install Adobe reader and OpenOffice with Java (these don't run full time but their update functions do).  Add a security suite like McAfee (which I do NOT recommend even if it is free from your internet provider) and you'll add even more.  Just make sure that the number of processes you allow to run does not hamper your system's performance such that YOU are inconvenienced.
    • This is an area where viruses and malware can often hurt you, so you could have a virus. ;)
  4. Not enough memory for number of applications running simultaneously.  A handy tool for determining what memory your system can use is the Crucial System Scanner.  It will scan your computer to find out what is already inside your system and will return upgrade recommendations.  This is provided by a memory manufacturer so they will offer to sell you the recommended memory, but you should check Newegg to see if you can get the same specification for less $$$.
  5. Computer processing speed is too slow for current generation applications.  This includes CPU speed, memory speed, and motherboard bus speeds.  Basically, if your computer was manufactured when MS Office XP (2002) was out, you've got to think that MS Office 2007 might be a little tougher for your PC to handle. Sticking with open source software can help you out here; open source is software written by user communities... who tend to be a little more conscientious about resource efficiency than major commercial software manufacturers.
The DIY page can walk you through fixing items 1 and 2.
Item 3 can be remedied by removing applications that you do not use. (Do this before you defragment.)  Also run malware scanners and antivirus products.    I have successfully cleaned some BAD computers using ESET NOD32 Antivirus along with some combination of Malwarebytes' AntiMalware, SUPERAntiSpyware and Spybot Search & Destroy.
Maybe it's time to REFRESH the system: If your computer is more than three years old you are likely experiencing several or all of the above symptoms.  If you would like to get a few more years out of your computer, I would recommend a fresh install of your operating system (OS). 
  • Backup your photos, music, and documents onto CDs or DVDs, or buy a portable hard drive (easiest, least time consuming).  I recently (Mar 2009) bought a 1TB external drive for under $120 (1TB is HUGE by most people's standards; equivalent to more than 200 DVDs or 1200 CDs).   
  • Once your data is backed up, get out your original OS install disc.  Since your old Windows XP disc is a few service packs old you should create a new updated disk.  All you need is:
    •  Your original Windows XP install disc,
    • a copy of the latest Windows XP Service Pack (SP3),  
    • RyanVM's latest Update Pack (go down the page to the Download section),  
    • the drivers for your hardware (extract them from your current installation with DriverGrabber)  
    • and a free tool called nLite.  With nLite you can slipstream the current service pack, hotfixes and drivers directly into the installation source, as well as add all of your registration data to create a fully unattended install disc.
  • Of course, you will need a CD or DVD burner and a blank disc.  And your computer will need to be configured to boot from your optical (CD/DVD) drive; this is a BIOS setting.
Detailed instructions for this process can be found on nLite's guide pages.  Or you can ask someone else (me or a friend) to do it for you.
This process can also be done for Vista; see
 PLEASE... AFTER you backup your old data and drivers and create your new install disc, but BEFORE you re-install your OS, vacuum out your computer case and fans.  You should even remove all of your components and re-seat them in their sockets to be sure everything will run properly.  This will give you the best (most reliable) results.