DALLAS (CNN/Money) - As far as desirable demographics go, you can't do much better than QuakeCon.

Roughly 7,000 people, mostly men in their late teens to mid-20s, are wandering the show floor at this annual convergence of "Quake" and "Doom" fans. More importantly, the people at the show are opinion makers, whose feedback in message boards, blogs and idle chatter can help make or break a product.

That's why a number of computer hardware companies, including Dell and Creative Labs, have chosen QuakeCon as the launching pad for their latest line of products.

"We have a huge assembly of the target audience 200 miles north of our headquarters," said Joe Curley, Dell's director of product marketing for Dimension desktops. "It'd be ridiculous not to take advantage of it."

Dell on Monday unveiled the XPS 600, a new workhorse PC made specifically for gamers, featuring dual graphics cards (rather than the standard single card found in most machines). The new machine begins at $3,099, but can cost much more depending on additional features such as expanded memory or an enhanced processing chip.

They're expensive machines, but they're tailor made for the gamers here, many of whom try to eke out every ounce of graphical and processing power from their PCs.

Creative, meanwhile, hopes to kick off the next generation of sound cards at QuakeCon. Monday, the company unveiled its new X-Fi line of cards, which it has spent four years developing at a cost of $100 million. The processing chip on X-Fi cards offers a significant upgrade from today's top-of-the-line audio processors, recreating the surround-sound experience in basic stereo headphones, enhancing audio quality and (according to the company) speeding up games.

QuakeCon attendees are the first to experience the new cards, with some people walking away with vouchers for a free card (which will retail for $280), once it becomes available later this month.

"You're looking at our bread and butter here," said Amy Stojsavljevic, a senior PR specialist for Creative. "This is a grass roots outreach for our core constituents. We want people to know we can deliver on what we promise.

Graphics chip manufacturer nVidia, meanwhile, is using the show to launch its latest video card. The GeForce 7800 GT uses a graphics processing chip that is very similar to the one that will be used in the PlayStation 3. Attendees have the chance to get hands-on time with the card, allowing them to determine if they're interested in spending the $449.

Peripheral manufacturers Razer and Logitech are also looking to leverage the show's enthusiast attendees with new product launches. Razer's new Copperhead gaming mouse is on display and, while not officially part of the show, Logitech is hosting an event nearby to showcase its new product line called the G-Series.

While a large number of QuakeCon attendees are hardware enthusiasts, everyone here is a gamer, so it's no surprise that publishers use the show to demo their upcoming games. Host id Software is letting fans get a hands-on trial of the upcoming "Quake 4" (well, the multiplayer components, at least). Activision (which publishes id's games) is also showing the forthcoming "Ultimate Spider Man". And publishers ranging from Vivendi to Electronic Arts are showing upcoming titles at nVidia's booth.

If you're not familiar with the gaming world, it's easy to dismiss the buying power of this crowd. That'd be a mistake.

According to a new study by Ziff Davis, there are 76.2 million gaming households in the U.S. 19.8 million of those have hardcore, enthusiast gamers in them, who spend $5.6 billon per year on games, hardware and peripherals. That works out to $282 per person per year. (Compare that to $111 for moderate gamers and $32 for casual gamers.)

With proper marketing, companies can turn those core gamers not only into buyers, but evangelists for their product line in the community.

"We've hit the threshold where people take this event very seriously," said Marty Stratton, director of business development for id Software. "We've grown to the point where this is one of the five events of the year [hardware companies] have to be at. ... If you want to make an impression on the gamers, this is where you do it."