Double Vision
Posted May 1, 2003

Some video pros insist that if you aren't seeing double, you aren't seeing at all. Multiple monitors are essential to pro DV work, they say, to free the preview and other windows from their tiny boxes. But few PCs ship equipped for dual-display driving. How can you get yours up to speed?

May 2003|Who would want double vision? I've wanted it, lots of times. For example, if you run out of pixels on one monitor, why not migrate some of those open windows to another monitor? I've used this technique when processing high-resolution digital images: put the camera's output image on one large high-resolution monitor and leave the camera controls or various PhotoShop palettes on another, smaller one. That also leaves space for an open Instant Message window on the "main" desktop so that when one of my friends makes a call, I'll see it immediately without scrambling to find the "answer" button. The same goes for editing in a program like Premiere, where in single-monitor settings you're confined to that tiny 4"x3" preview window. And that's why video production workstations like those from Media 100 invariably ship with two monitors. Video pros insist it's the only real way to see what you're doing.

Building my multiple-monitor dream system, I like to use one of NEC's cool, SXGA resolution 20-inch LCD panels such as the LCD2010X ($1499 on the Web) as the main screen and either another LCD for the second screen or one of Sony's ultra-high resolution (max, 2340x1440) 24-inch CRT monitors like the GDM-FW900 ($1999.99 at www. If the application demands an even bigger screen, I'll grab a little projector and then…But hold on, maybe I'm getting ahead of myself.

Doubling Down
If you're like most people, you probably have only one video output in your computer. And if you're a notebook power user, you certainly only have one video output—but depending upon your operating system, you can use that video output in conjunction with your laptop's screen to expand your view of your work. But back to the desktop world—like I said, most of these computers have only one video output and with that output plugged into a single monitor, their view is limited to what can be shown on that one monitor.

If you want to get a quick dose of double vision, grab a video distribution amp (DA) like the Extron ADA6 ($795 list). I've used one of these for years. It lies on the floor under my desk, constantly connected to one of my computer's video outputs, and whenever I have a need to see the same image on my 20-inch monitor blown up to 100 inches or more, I plug one of the ADA6's six outputs into a projector. The projector zoom lens can easily expand what's on my screen on a nearby, conveniently blank wall or a handy screen that gives me two views: the small one on my desktop monitor, and larger one on the wall. However, both of those images have essentially the same content.

Sometimes I need to show a different image on two separate monitors, and a simple video distribution amp can't do that since it only takes what the computer's graphics card gives it. In that case, I need to use a different RGB graphics output. Leaving the main graphics card plugged into the Extron ADA6, I can plug another display device into another RGB output and then let the OS divide the work on to multiple, separate screens. That's the key to success— divide and conquer—but it takes a special card and lots of cooperation between the card and the OS. Most of the time, if you replace the standard graphics card in your computer with another one that can provide more resolution, faster updates for games or video processing and more grayscales, or even one with 3D graphics capabilities, you're still left with only one video output.

Mac in the Mirror
This is one case where the many users of Apple Power Macs have a real advantage over PC users. Some of the older PCI (peripheral component interconnect) PowerMacs had their graphics controller built into the motherboard, controlling one of the quirky Mac video connectors. Just about any time you inserted an add-on, third-party video card into a free PCI slot, you were all ready to drive multiple monitors. I still use a couple of PCI-equipped Power Macs with the old Mac-only video output going into a Mac monitor while using, at the same time, one of the other video outputs from the add-on PCI graphics card, to drive an additional standard 15-pin RGB monitor or projector.

The Mac OS—dating back to 8.x—can easily support multiple monitors as long as you have the right graphics cards installed. That's right, you can even add PCI graphics cards to the newer Power Macs— leaving the factory-installed card in place. When Apple's OS senses (and sensing means having all the display devices powered on and connected to graphics cards before booting the Mac) multiple monitors, it shows an "Arrangement" tab in the monitor Control Panel or System Preference window. You can then use that arrangement feature to determine what resolution your multiple monitors will display and whether or not they will "mirror" each other or reside next to each other in the overall expanded display space.

"Mirroring" doesn't do any more than provide an additional monitor or a projector showing the same thing on both screens—something that a simple DA can also do. However, being able to "arrange" the monitors side by side is a great workspace-organizing tool—especially when one of those monitors is a super high-resolution device like Sony's FW900 CRT monitor or Apple's HD Cinema display. (See Bohannon's "LCD versus CRT for the DV Studio,"

I have successfully installed ATI's current Radeon 7000 series "Mac Edition" graphics cards in both the older and in the newest Power Macs. The only requirements for this installation are that the Mac's PCI bus be a 33 or 66mHz standard PCI 2.1 bus and that the OS be at least OS9. There doesn't seem to be any restriction as to how many cards you can install, either; as long as you have empty PCI slots, it appears that you can keep installing graphics cards and driving more monitors. But so far I've only done it with two cards and two monitors in one machine.

Unfortunately, there doesn't seem to be any way to add multiple monitor capability to Apple's iMac, and that's where you really need it, given how small those screens tend to be, especially in the one-piece consumer boxes. My iMac has a separate 15-pin RGB output port on the back, but it can only be used for mirroring the iMac's little CRT image onto a large screen driven by a projector or plasma. The iMac's built-in graphics card will not support multiple monitors and the OS will not let the "Arrangement" tab appear. I know of no way to upgrade the iMac's graphics abilities to support multiple monitors—but I'm hoping someone clever will come up with something.

Driving the View, PC-Style
So Macs can easily support multiple monitors, but how about PCs? My PC testbed is a heavily upgraded older desktop tower system made by San Diego-based systems integrator Datel Systems. That's Datel, not Dell, and whether or not anyone has heard of them outside of San Diego, they're locally well-known, and the system I've used (based on a AMD K6 processor) has worked fine over the years. Anyway, the old Datel has three extra PCI slots besides the PCI graphics card plugged into its motherboard. All of which makes it a perfect system for a graphics card upgrade, especially since the current graphics card is practically the only original piece still in the machine.

I obtained one of ATI's 7500 graphics cards for PCs running Windows, but just picking the appropriate card was a bit of an exercise. There are several different kinds of graphics cards for the PC available from ATI, as well as from NVIDIA and others. I wanted to try one of ATI's cards since I've used their cards with success on the Mac side. Anyway, for the PC you can choose between the Rage128Pro, Radeon, Radeon 7000, 7200, 7500, 8500, 9000, 9500, and 9700 with various versions in between such as All in Wonder Radeon, All in Wonder Radeon 7500, All in Wonder Radeon 8500, and so forth.

Choices, choices, too many choices… but since the old Datel uses a slower PCI (not the latest and fastest AGP, which stands for Accelerated Graphics Port) configuration for graphics cards and I wanted to be able to drive two monitors at once, I chose the Radeon 7500 card for PCI (only $79), which supports two monitors (one DVI and one RGB) at up to 2048x1536 resolution. ATI offers the Radeon 7500 for both PCI and AGP slots driven by Intel, AMD, or compatible processors. ATI has faster cards than the 7500 and cards with more on-board memory, but unfortunately, those cards are only for AGP graphics slots—not the slower PCI. But that's okay, my old Datel machine probably wouldn't know the difference anyway— it's pretty much bus-limited now. (For more on AGP and PCI graphics cards, see Nick Kortan's "Stacking the Deck,"

Other graphics cards manufacturers also support multiple or dual monitors—Matrox with their DualHead-enabled Parhelia and Millennium cards; NVIDIA, a famous name for both Mac and PC graphics cards, with the GeForce4 and GeForce4 MX graphics cards—starting at about the same price as ATI's Radeon 7500. However, the multiple monitor-ready GeForce cards only come in an AGP flavor, which is not compatible with my Datel, or any other PCI-only machine. In addition, the information I've seen for the GeForce4 cards indicates that they can drive two CRTs with up to 2048x1536 pixels each or two digital flat panels at 1280x1024 resolutions. Some of the cards seem to come with DVI connectors and some with 15-pin RGBs. Even NVIDIA's Web page says to make sure that the card you buy can do the things you want it to do, which is easier said than done. I could spend an entire day at the local CompUSA store reading the outside of the boxes and then going to the manufacturers' Web sites to make sure and still not know if the card I wanted to buy would drive the collection of monitors I have.

No Room at the Fins
At the end of my frustrating investigations, I got the ATI Radeon card (along with the hope that I wouldn't have to take it back and trade it in for another one that would actually do what I wanted) which supported two outputs—one with the standard 15-pin analog RGB connector and the other with a 30-pin DVI digital connector. Then I had to install the card, and I found that was a much harder job than installing a similar card into a Mac. Whereas the Macs all have rather standard software and PCI configurations—naturally, since they're all made by the same manufacturer—a PC can come in a wide variety of flavors and configurations. In addition, there are various lengths of PCI bus slots to worry about. The existing PCI graphics card in the Datel was a "half-length" card, while the Radeon 7500 card was a bit longer than that, but not a "full-length" card—maybe they call it a five-eighths card. Who knows…

Anyway, if I had enough room for a full-length PCI card, then I could have installed one of Appian Graphics' "AppianX" cards, which can drive four separate 1920x1200 monitors. Appian also offers the Typhoon and the Hurricane that both drive two 2048x1536 displays, or the Rushmore, which drives four separate 2048x1536 displays. The PCI-based AppianX card costs about $835 online—a lot more than the under-$100 ATI card, but it's more versatile and capable.

Alas, there was no room under the Datel's hood and actually not even enough room for the ATI card. After juggling cards around and moving the ATI card to the last PCI slot near the bottom of the motherboard, the end of the graphics card just collided with the CPU cooler on top of the AMD K6 processor. What to do? I need at least two monitors!

Well it's just a CPU cooler and it has a lot of cooling fins along with a big fan on top, so I figured it could do without a few fins and still survive. I got out my trusty snippers and trimmed fins until the card could drop into place without hitting the remaining fins on the CPU cooler. I don't know if anyone (except me) would recommend this procedure, but the card eventually fit and the old Datel is still ticking just fine. Once the card was safely in place, the OS had to be reconfigured and the proper drivers installed. That is a tricky process, too—not as simple as the work required to update the Mac's drivers. Maybe Windows gets in the way, maybe it doesn't; but old drivers surely do, and ATI's instructions say to be sure to uninstall the existing drivers (and to update the AGP drivers if you have that version) before putting the new card in and before trying to install the new drivers. And yes, you have to take the existing graphics card out first, too…PCs are so difficult.

With the fins snipped, new card installed, and the machine rebooted and working again (but with weird colors due to some default "no driver" mode), I had to install the new drivers to get all the performance and color they're capable of and to have multiple monitor support. ATI says to not use the Windows "found new hardware" wizard—and indeed, it doesn't work if you try. You have to exit from Windows, install new hardware programs, and then run the ATI install CD all by itself. However, if you do follow all of their instructions, the software will work well enough after restarting.

Then I discovered that the Mac version does work easier than the PC version of essentially the same 7000 series Radeon card. With the Mac in either OS9 or X you can have two or more monitors with different resolutions. However, with the PC, I found that the system only allowed two monitors with the exact same resolution. For example, if you have an 800x600 monitor on the 15-pin RGB port and you attach a huge, high-resolution, 1920x1200 monitor to the DVI port on the card (maybe by using a 15-pin analog-to-30 pin DVI adapter that allows you to get onto the available analog pins hidden among all the digital pins), you will find that you can only use 800x600 pixels on the high-resolution monitor. With both monitors forced into 800x600 mode, the drivers made up a big side-by-side or top-and-bottom desktop with 1600x600 pixels and then divided that equally between the two monitors. You can change the resolution of both monitors around, but only by what is allowed on both monitors—unlike the Mac, which allows separate, independent monitor resolution.

I called ATI to find out why this limitation existed and the first question they asked was what version of Windows was running. I have Windows 2000 Professional running on the old Datel and I thought that was sufficient. No way, they answered—ATI says that only if you're running XP or ME will you be able to run two monitors at different resolutions. If you're running Windows 2000, both monitors have to be set to the same resolution. If you're running Windows 98 or NT, you're probably totally out of luck unless you can find a patch to the ATI drivers on their Web site.

The other graphics cards manufacturers seem to have similar OS restrictions; some cards from some companies will support NT and Windows 2000 and some support XP and ME or some mix of the four including support for poor old Windows 98. Gee, I thought that it was hard enough to switch from Mac's OS 9 to X, but the PC guys seem to have a much harder time supporting all of those different versions of Windows.

Hello Walls
However, at the end of the day, I had my Datel up and running with multiple monitors and even with Windows 2000, just being able to spread the workspace out evenly over two 1024x768 monitors made a big difference. If I had two distinct 2048x1536 monitors I'd be really happy, but that wasn't the plan. I wanted to operate a couple of monitors in different sizes and resolutions. Then I discovered another use for the "extra" video output port in the Radeon card: it can drive projectors just as well as monitors.

Ever need a lightweight, wall-hanging, paper-thin, 50-inch monitor in your office? It's easy. I mounted one of Dell's (that's Dell, not Datel) newest little 3.5-pound DLP projectors, the 3200MP ($2199 at under my desk. This is an XGA resolution 1024x768 pixel projector with a good zoom lens that makes about 1300 lumens with a lot of contrast. So with one of the Radeon's ports connected to the desktop monitor and the other connected to the Dell projector under the desk, I could easily make a 50-inch image on a Lumenstar compact screen from TRaC Associates mounted just a short distance away.

The Dell is quiet, too, not at all noisy like some of the early DLP projectors were, and with a projector's high contrast image shining on the super high-contrast Lumenstar screen. there was no problem seeing the on-screen image, even in a room with a lot of ambient light. In addition to its high contrast, the Lumenstar screen has a wide viewing angle, too—so regardless of where the viewer was positioned, the on-screen image was sharp, clear, and had high contrast…such a deal, in an alternative route to multi-screen satisfaction.

Adobe Systems, Inc.
Appian Graphics
Apple Computer, Inc.
Datel Systems, Inc.
Dell Computer Corporation
Extron Electronics
Matrox Electronic Systems, Ltd.
Sony Corporation
TRaC Associates, LLC