YOU JUST WANT to pop a beer and a Martian or two. Instead you must answer incomprehensible questions about "drivers that have not been certified," after which you discover your Windows 95 machine does not work quite the way it used to.
That kind of thing can happen all too easily with Directx, a Microsoft Corp. technology devised to help developers create games for the fat but fancy new Windows 95 system without sacrificing the performance they got from the lean but ugly old DOS.
Special Directx software drivers manage video, audio, joysticks and other hardware, eliminating the need for games to communicate directly with dozens of different devices and making program installation a snap.
Or so goes the promise.
Today, dozens of programs use Directx, and on some computers they work almost as seamlessly as Microsoft claims. But with many machines, installing Directx will disable advanced features like TV tuners and more mundane ones like on-the-fly resolution switching.
With a few, buggy drivers can cause the computer to begin behaving erratically.
A snap this is not.
At the root of most Directx evils is the fact that most of the software drivers typically supplied on game disks address the computer's graphics chip rather than the entire video subsystem it anchors.
Because the makers of cards and computers that use these chips employ clever stratagems to get the most from them, features in their software are often missing from Directx's least-common-denominator code.
Installation is another problem.
Because Directx comes in versions numbered 1, 2 and 3 that do not easily reveal themselves to the user, different programs may install different sets of drivers. Despite much finger-pointing between hardware and software makers and blame enough to go around, the good news is that the problems are rarely fatal or irreversible.
The trick is knowing what to do about them.
Spotting Directx software is not easy. Not all games designed for Windows 95 use Directx, and not all Directx programs are games.
Packages rarely offer clues, though a close reading of the manual or read-me file might help. The surest way to know is to decline the installation program if asked and use Windows Explorer to scan the CD-ROM.
If you see a Directx folder, bingo.
The software's manual or read-me files might tell you if your video card or chip produces known problems.
Before you install a Directx program, try to find updated information and software drivers on the Web sites of the maker of your video card, computer, or, as a last resort, video chip.
What you need to download and install might not be obvious, because different cards from a single manufacturer may have similar or identical names, and identical cards are often sold under different names. With older cards, you might have to settle for the drivers that come with the game.
Installation might beget more confusion.
Directx drivers are supposed to be tested and "certified" by Microsoft. Unfortunately, some certified drivers do not work properly with every card, while uncertified drivers might work just fine.
The installation program typically warns you that a particular driver is uncertified and asks if you want to replace it with a certified version.
"Yes" is the logical answer, but it might be the wrong one, because a card maker's uncertified late-model driver is sometimes a better bet than the outdated but certified one on the game disk. Head spinning yet?
The drivers tend to trickle up from the chip maker to the card maker. For example, systems using the popular Trio 64V+ and Virge chips from S3 Inc. might produce strange results after installing Directx unless you install a certified driver available from the Web site at www.s3.com, which may become unavailable for a few days while the corporate headquarters moves.
That driver might disable some video features, but card makers should eventually offer versions that restore them.
Pub Date: 1/13/97