The Voltage in the Dell

A mysterious current led me to the perfect multipurpose monitor

3 min read

I just can’t squeeze two screens into my living-room home office, sharing it as I do with two small boys, their train sets and games, and a tank full of aquatic frogs. So last year I sought out one display that would do everything. My seemingly simple search turned into an engineering detective story that would ultimately involve three companies, four monitors, a helpful executive, and a tutorial on the nature of electric current.

It wasn’t much of a quest at first: I quickly settled on a US $999 27â''inch Dell 2707WFP with decent resolution, which I could plug my digital cable box directly into. Then I noticed horizontal pink bands that moved slowly through the television picture. The problem stumped customer service at both Dell and Time Warner Cable. Still, Dell swapped the monitor three times. Time Warner changed my set-top box and then my cables. Nothing worked. It was time for Google.

Photo-illustration: Hum Bars: Bill Whitlock; Monitor: Dell

Pink hum bars, visible in the white lettering above, proved a nearly intractable problem in one Dell monitor model.

I searched on ”slow pink bars” and found my problem: a ground loop—the same condition that causes a loud hum in some stereo equipment. When there are small voltage differences in the wiring that connects different pieces of electrical equipment, an unintended current will flow through the system. In my case it ran through a printed circuit board within the monitor, showing as slow-moving bands called hum bars, which are sometimes pink.

With my diagnosis, I also found Jensen Transformers, in Chatsworth, Calif., known throughout the Internet as the king of ground-loop fixers. Jensen sold me a $60 ground-loop isolator that attached to my television cable. It worked, but it also blocked the kids’ cable cartoon channels. Jensen sent another model of isolator that had the same problem. Not giving up, the company sent—at its own expense—a $500 ”humbucker.” When that didn’t work, Jensen’s president, Bill Whitlock, called to take me on a step-by-step test to find the exact point in my system where the pink gremlins were invading. He also told me that a properly designed monitor would have routed the ground hum away from the video circuitry. Visible bars were evidence of what he called a ”head-slapping design flaw.”

Whitlock wondered aloud whether anyone teaches ground loops in engineering schools these days. Designers, he says, apparently come out of places like MIT thinking that ground wire equals zero current, end of story. Most designers don’t know that they can build a $15 test device that would vastly improve their designs.

I called Dell once again. The company generously responded with an upgrade to a far better monitor—the 3008WFP, a 30â''inch model that had come out just two weeks earlier and costs twice as much as my original. Its resolution is so good I can keep five or six windows open at once. It also doubles as a true HD 1080 television.

Last year, the only monitors with 4-megapixel (2560-by-1600) resolution were designed strictly for doctors and graphics artists. They were expensive, yet didn’t easily replace a TV, having only a single digital visual interface (DVI) input. This year, however, Dell realized that a simple modification would make its highest-end monitor ideal for video gaming and plain old television watching as well as computing. Dell gave it seven inputs in all, including high-definition multimedia interface, display port, DVI, component video (the familiar triad of red, green, and blue plugs), and composite video (using a single yellow RCA connector). The picture is so crisp, and the colors so vivid, that the 3008 has become the kids’ favorite set. In fact, they complain bitterly when Mom takes it back for her obsessive multitasking.

All this technology doesn’t come cheap. The monitor itself costs about $1964, and for peak resolution you need a high-end graphics card. And this is, of course, television without a tuner and without built-in sound. Add a cable or satellite box and external speakers, though, and it’s good to go.

Would I buy one next time around? For me the 3008 is absolutely worth the full freight. If a television is all you’re looking for, you can get a 42-inch high-end set for the same money. But if you want one screen that does it all and does it very well, it’s worth going into the red. Just stay out of the pink.

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