I promised to discuss other PC upgrade options this week, so here we go.

If all you’re lacking is a CD or DVD burner or the ability to use data or video DVDs in your computer, take heart: You can buy a DVD burner that reads and writes to both DVDs and CDs for about $41. Installing one is usually just a matter of removing your old CD drive and putting the new one in its place, then installing some software.

Processors (CPUs) are trickier to upgrade. First, determine what type of processor you have and the type of “socket” it is in. Then, find the fastest processor your motherboard can handle. Finally, figure out whether processor is still available for purchase, as technology moves fast. Stock runs dry quickly for parts like this.

Swapping out a processor can be physically challenging. You must remove the fan and heat sink that keeps your processor cool, then remove the processor from the motherboard. Then, you’ll install the new processor with some heat-transfer paste and a new cooling fan. It’s certainly affordable and achievable, but don’t be shy about asking a pro for advice first.

If you like to play the latest graphically intense games, you’ll need a good video card. Modern video cards do far more than simply paint pictures on your monitor. They can also perform a considerable amount of the processing that your CPU might have to do otherwise, such as decoding DVDs and doing advanced algorithms to draw smooth three-dimensional shapes. It’s usually easy to find inexpensive upgrades for video cards, even for older PCs.

If you’re running low on hard-drive space, you can either add an additional hard drive or replace your current one. This can be time-consuming and technical if you want to keep all your existing data and simply end up with more space. Consult a pro if you’re in doubt. You can add a significant amount of space for $50-$150.

Finally, this is what I tell many people who are looking for an upgrade out of frustration with their current computer: Consider wiping out your hard drive and reloading everything. Your computer shouldn’t be much slower now than it was when you first purchased it. If it is, it might be time to start fresh, without months or years of accumulated litter on your hard drive and the ghosts of former programs lurking about. If you can’t do it yourself, any professional worth his salt should be able to. Have a good backup of all your data, including your address books, e-mail accounts, Web “Favorites,” financial software files, purchased and downloaded music and software, etc. Lots of places refuse to perform backups or charge exorbitant fees.

On the subject of upgrades, many of you have noticed recently that AVG Anti-Virus is persistently requesting that you upgrade to its latest version, 8.0. However, it’s tricky to navigate its advertisements to find the free version of the upgrade. The fastest route I’ve found is to follow the link below. Once you’re there, look for a “Get it now!” button for AVG Anti-Virus Free Edition.

On the next page, you’re presented with several compelling reasons to purchase its complete suite of products instead. If you’re still reasonably convinced that the free version is what you’re seeking, click the link that says “Continue to AVG free download.” You are solicited once again on the following page, but press on. Links to the download are next.

Launch pad to get to AVG Anti-Virus Free Edition: http://free.grisoft.com/

Parts and pieces for upgrades can be found locally at Computer Parts USA: http://www.cpu.com