Bring an old PC back up to speed

— -- Over time, your computer's performance will slow down. But that doesn't mean you need a new machine. Maybe you simply need to fix your clunker.

My friend, Ed, has a homebuilt machine. Seven years later, it's still fast and reliable. Over the years, he's replaced the DVD drive (twice) and the power supply. He added memory, too, which was cheap. He also reinstalled Windows once. I've got more about that below.

If you're handy, or willing to learn to fix your computer, good machines last for years. Repair shops usually aren't cost-effective. Replacing a hard drive could run $300 or more. That's approaching the cost of a new computer.

A computer could be slow because of its hardware, software or both. Say your computer used to be fast and then you added programs. Maybe you overwhelmed the RAM (random access memory). If you have Windows XP, 1 gigabyte of memory should handle everything. If necessary, add some memory.

Still slow? Your microprocessor may be struggling. Theoretically, you could update the chip, but don't try. Put up with it, or buy a computer with horsepower.

Got Windows Vista? Raise your memory to 2GB if you have a 32-bit machine. Owners of 64-bit machines can go to 4GB. Actually, you can go a lot higher. That's the big advantage of 64-bit computers. But you're probably just wasting your money adding more that 4GB of memory.

(Don't know 32 and 64 from Adam's cat? To see which kind of computer you have, click Start, then Control Panel. In the left pane, be sure you're in Classic View. Double-click System. Under System, find "System type.")

The Vista video system needs 128 megabytes of dedicated video memory, minimum. If you think you need more, go to 256MB. That is, if you have a video card. They're easy to swap out. Stop at 256MB, unless you're a serious gamer. If the video system is built into the motherboard, forget it, you won't be able to upgrade the video memory.

But there's one other thing. A full hard drive, or one nearly so, will perform poorly. At the least, you need a gigabyte of free space. Add a second hard drive, if necessary. Or, kill programs you don't use. That will probably be most of them!