(MONEY Magazine) – IS YOUR COMPUTER UNFIT FOR EVEN THE SLOW LANE OF THE INformation superhighway? Do you long to launch Windows 95, Netscape and other powerful, memory-hungry new programs? If so, you have two basic options: Soup up your old wheezer, or junk it and get a new one.

Upgrading is cheaper by far, but it makes sense only if your machine already has fairly respectable brainpower. To run modern software at better than glacial speed, says computer consultant Steve Malloy of Advanced Systems in East Greenwich, R.I., don't bother with anything slower than a 486 microprocessor. A Pentium is preferable. Macintosh users will need a machine powered by a 68040 chip or its speedier successor, the PowerPC. If you meet those requirements, consider these three cost-effective upgrades: added random-access memory (RAM), a CD-ROM drive and a new, larger-capacity hard drive. For details, see the table on page 169.

On the other hand, if your machine is an IBM-compatible powered by a 1980s vintage 286 or 386 microchip or a Macintosh running on a 68020 or 68030 chip, don't waste time tinkering. If you aren't content with your old computer, it makes more sense simply to buy a new one.

But don't just toss your old machine out with yesterday's floppy disks. Most medium-size and large cities now have stores that buy used computers or sell them on consignment. (You'll find them in the Yellow Pages.) Don't expect to get much money, though. For example, a 386-powered IBM-compatible that sold for $2,400 three years ago is probably worth no more than $400 today.

You may get more satisfaction by donating your computer to charity and writing off its market value as a charitable deduction. To determine market value, check what comparable computers are selling for in a magazine like Computer Shopper. (If the value is more than $250, don't forget to get written confirmation of your donation from the recipient.)

Where can you give away your old computer? A good starting point is your local school system. Many schools need computers, although they won't always accept equipment that isn't compatible with what they already have.

Another option is to call Gifts in Kind America, a nonprofit group whose Recycle Technology program matches donors' computers with worthy causes. The group will give you the names of three organizations in your area that need your equipment. (Call 703-836-2121 or E-mail ProductDonations@GiftsInKind.org.)