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I always like it when a manufacturer innovates to make somethinggood even better, especially when it’s at a competitive price. Suchis the case with the new DH-MAX from ProMax Systems. VideoSystems readers have heard it many times: With today’snonlinear video and audio editing applications, two computermonitors are the key to many happy hours. Next to buying new andbetter cables or adding RAM to my computer editing system, theupgrade to dual-monitor display has reaped me the biggest return inproductivity.

Until now, Mac users have had to suffer by taking up one of thefew PCI slots on the G4 machines in addition to the included ATImonitor card, which uses the Advanced Graphics Protocol (AGP) slot.At the same time, Windows users were paying an arm and a leg forsolutions like the Appian Jeronimo card, which costs more thantwice as much as the new DH-MAX. But no matter what platform you’reusing, stretching one application across two monitors or viewingtwo applications at once is the goal.

The DH-MAX takes that goal a step further. The board allows awide variety of configurations, not just two RGB monitors. Userscan tie together an RGB monitor and an analog flat panel, an RGBand one NTSC/PAL video monitor, or two analog flat panels, etc.It’s nice to have options. Just contact the company to make sureyour monitor is 100% compatible.

ProMax Systems, working with Montreal-based Matrox Graphics,which makes and markets a PC version, has created the new productin the DH-MAX. This dual-display graphics solution is essentiallydesigned for Power Mac G4 and G4 Cube users. (There have beenreports on the ‘Net of users getting the board to work withexternal boxes that have a Mac OS-compatible AGP slot, but thiscould not be confirmed at press time.) The DH-MAX is anAGP-compatible graphics card based on the Matrox G400 chip. This isthe same technology that powers the popular Matrox Millennium G400graphics cards. ProMax created the Mac-based drivers and supportsthe board with both marketing and technical support.

By writing computer code directly to the Power Mac G4’shardware, the DH-MAX drivers leverage the 32MB of high-bandwidthSGRAM (graphics RAM) and 300MHz RAMDAC output to providerazor-sharp images, text, and video inlay in millions of colorswith resolutions up to 2048×1536. A unique 256bit DualBuscombined with a 128bit memory bus helps the board achieve fastgraphic redraw and the acceleration of QuickTime, QuickDraw3D, andOpen GL standards. ProMax says the new 3.0 drivers will alsosupport Open GL more fully, which will delight both 3D animatorsand serious gamers.

The install was almost painless but illustrated the only majordrawback (besides some problems I’ll discuss later) of my new G4:The PCI slots are too few and poorly arranged. The four slots sitat the bottom of the vertically oriented motherboard — tooclose to the hard drives for my taste. This and the heat variousboards generate means you need to give some thought to thearrangement of your machine’s boards.

I’ve got mine set up as follows: The bottom slot is empty, thena Digi 001 audio board, then an empty slot, then a UW-SCSI board,which unfortunately abuts the AGP slot that houses the DH-MAX. Thedual-monitor capability is a no-brainer for Power Mac G4 Cubeowners, since the 8″×8″ Mac has one AGP slot and nada for PCIslots.

DH-MAX comes with a CD-ROM with the latest drivers and follows astandard install routine. One of the challenges is that thedocumentation actually leads the user through the wrong steps ofinstallation, according to technical support. Users should installthe drivers before taking out the ATI card and installing theDH-MAX board. The docs have you doing it the other way around.

After restarting, you have a number of options at your disposal.Determine which monitor will boot with the system, and change theposition of the monitor image, color, and resolution. Once I haddisabled all my old ATI drivers I was all set — or so Ithought.

The problem was that the board’s drivers refused to recognize myolder twin Compaq 171 FS RGB monitors. A quick call to the freetech support 800 number (a growing rarity) addressed this. And bythe time you read this, a new version (3.0) of the drivers thatwill supposedly recognize almost all monitors will be available toregistered users. Just to make sure, give ProMax a call beforepurchasing. The final drawback: The drivers do not yet support DVDplayback, although this too is reportedly being addressed.

The DH-MAX drivers also provide Video Out on the second headusing supplied Composite/S-Video cable. This enables you to extendyour desktop applications or video out to an external NTSC/PALvideo monitor.

This 2.0 version improves video acceleration and QuickTimeacceleration. Also, the recently developed DH-MAX control panellets you check the version of the card, update your ROM, and checkthe acceleration of your system.

I liked the fine-tuning adjustments for hue, saturation,brightness, and contrast for the Composite and S-Video outputs.Nice touch. One other recent enhancement is that the board nolonger has a noisy fan but now sports an effective heat sink overthe main chip.

At this price point ($299) I would have been satisfied withbeing able to add a second RGB monitor without taking up anotherslot, while at the same time taking full advantage of AGPtechnology. But ProMax takes this a step further and includes aunique analog video cable that plugs into one of the two 15-pin VGAports of the computer board and provides both a Composite RCAoutput and an S-Video cable. This allows you to hook up toa standard or Super VHS NTSC or PAL monitor, television, orVTR.

This feature can be used in a boardroom sales presentation oreducational environment where a laptop controls a PowerPointpresentation. The DH-MAX’s second output displays it all on alarge-screen monitor. But what I find most useful is the ability tocreate a videotaped record of an application’s interface as it isused. I can see some ingenious entrepreneur using this to createlow-cost tutorial tapes. One wouldn’t have to sell too many tocover the unit’s cost.

In addition to the enhanced productivity that two computermonitors inspire, there are also the impressed looks I get asclients and visitors stop by my project studio. There’s somethingabout having two identical monitors side by side that says,“I’m a professional who’s serious about my work.”

Based on its reputation and how rapidly the company has releasednew drivers, it’s easy to see that ProMax is serious aboutaddressing user issues and following through on improving itsproduct (with DVD support, etc.). At less than $300, I’m hardpressed to figure why any serious A/V professional wouldn’t wantthe increased desktop real estate the new DH-MAX and, for PC users,the Matrox Dual-Head board provide.

After years of hearing it, I’m finally seeing the truth in theold adage “Two heads are better than one.” Videoprofessionals and amateurs alike should definitely give thisproduct a double take.

Tom Patrick McAuliffe also writes “The Public Eye”covering the government A/V community for Video Systemsevery month. Reach him at


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Company: ProMax Systems Irvine, Calif.;949-727-3977
Product: DH-MAX graphics card
Features: Enables dual-monitor display for the Power MacG4 or G4 Cube and requires no PCI slot; supports video out to RGBmonitors, NTSC/PAL monitors, analog flat panels, etc.
Price: $299