It doesn’t seem so long ago that buying a new Mac often required buying a new display to go with it -- and there were plenty to choose from. Flash forward to the present and Apple is selling more notebooks and iMacs, which has all but negated the need for a separate monitor with many users. But for the few, the proud who still need one, here’s a quick look at your options.

From the Macintosh Portrait Display introduced for desktop publishers in March, 1989 to today’s 27-inch Thunderbolt Display, Apple has kept busy producing a wide array of monitors to plug into their Mac computers over the years. But a funny thing happened 13 years ago this month -- a little Bondi blue marvel called the iMac set the stage for an external display to become less important as Cupertino retreated back to the all-in-one design that made the original Macintosh so popular in 1984.

Of course, there are plenty of us who still need to get work done with an external display. Mac mini and Mac Pro users immediately spring to mind, but many MacBook Pro users also prefer to dock their laptop while at home or the office to enjoy a larger view of what they’re working on. (Never mind the power user who thinks nothing of two or even three displays for their work.)

While there is but a single choice of external display from Apple today, thankfully other manufacturers are still busy pumping out Mac-friendly monitors. Here are some tips for finding the one that fits you like a glove.

Apple Thunderbolt Display

According to the Mactracker database, Apple has produced 23 different displays over the last 22 years, not counting those included with all-in-one systems like the iMac. Prior to this summer, Cupertino offered at least a few different size options (usually small, medium and large), but in a sign of the times, today there is only one: The $999 27-inch Apple Thunderbolt Display.

Nearly a dead ringer for a 27-inch iMac, Apple’s Thunderbolt Display also features many of the same peripheral connections -- three powered USB 2.0 ports, FireWire 800, Gigabit Ethernet and yes, a single Thunderbolt port for jacking into this year’s MacBook Air, MacBook Pro, Mac mini and iMac models. Thunderbolt peripherals such as RAID storage devices can be daisy-chained, with the display usually the last in line.

Packing a thin film transistor (TFT) active-matrix liquid crystal display (LCD) with in-plane switching (IPS), the Apple Thunderbolt Display is a great match for any current model Mac. Unfortunately, owners of older Macs built before Thunderbolt (including the most recent Mac Pro) aren’t getting an invitation to this party, forced to look elsewhere for some love and affection -- or to buy a new Mac, which Apple would no doubt prefer.

Back to the Future

Thankfully, there are literally hundreds of choices available from private sellers on auction sites such as eBay.com, where you can pick up older Apple Cinema Displays from the last few generations for a fraction of their original price -- and some even come with the enticement of free shipping, which is not insignificant for such heavy, bulky items.

Those who shun Thunderbolt can also pick up a bargain on last year’s 27-inch LED Cinema Display, which Apple is currently offering as a certified refurbished sale for $849 if you act quickly. Apple resellers are also likely to have the same model brand new in the box for just a few bucks more, including B&H Photo ($899 at the moment), MacMall, BestBuy.com and Amazon.com (all $939.99 at this writing).

Avoiding the “Apple Tax”

While most of us can’t live without our Apple computers, when it comes to external displays, we tend have less of an allegiance to the fruit -- especially if you’re not in the market for something as expansive as 27 inches or lack the necessary Thunderbolt port to plug into. Apple displays have historically been on the costlier side, although prices have fallen with the newest model.

For example, a few years back we picked up a 30-inch Dell display for about $1,000 -- a fraction of what Apple’s comparable 30-inch Cinema Display was selling for at the time ($3,299 SRP), and it continues to serve up bright, crystal-clear imagery. In order to drive such a large display at the highest 2560x1600 resolution, we also had to pick up the $99 Mini DisplayPort to Dual-Link DVI Adapter, which works well -- aside from occasional (and well-documented) issues with the adapter losing sync, cleared up by simply sleeping and waking the monitor again.

The current lineup of Dell monitors support HDMI, DVD-D and VGA with DisplayPort on several models, which means in almost all cases you’ll need some kind of adapter to make it work with your Mac. (One obvious exception is the newer Mac mini, which will work out of the box via HDMI.) In all cases, Mac users will need a Mini DisplayPort to DisplayPort cable (or adapter) to make the connection -- Monoprice.com offers four sizes (from three-foot to 15-foot) for just a few bucks.

NEC is another favorite choice for external displays, with options ranging from a number of thrifty 17-inch monitors, all the way up to a few pricy 30-inch models topping out at over $2500 (retail price, of course). NEC’s 27-inch models make the Apple Thunderbolt Display look like a bargain at $1399 and $1649, respectively, but buyers can shave a few bucks off those prices through online resellers like Amazon. Many of NEC’s displays also come with DisplayPort as well.

Of course, there are plenty of great options also available from suppliers such as Acer, ViewSonic, LaCie and more -- your best bet is to research what others are using (through Google, Bing or online forums), then head to your nearest computer dealer to see them in action, whenever possible. You’ll particularly want to pay attention to the comments of fellow Mac users to ward off any potential compatibility issues, although thankfully, these days most displays work just fine with the appropriate cables.

Other Considerations

As always, buying a new display for your Mac comes down to how much screen size you can afford and at what quality. Widescreen displays with a cinema-style 16:9 aspect ratio have quickly become the norm, but when buying online you’ll want to verify before clicking on the checkout button.

You’ll also want to weigh the benefits of display types -- cheaper LCD displays tend to put out a less vibrant image that may not properly represent white levels, while LED-enhanced models cost more but produce a brighter, more evenly lit image with accurate colors -- especially when you add an IPS panel to the mix.

Finally, if you want a future-proofed display equipped with Thunderbolt, your choices are currently narrowed to exactly one: Apple’s $999 behemoth is the only game in town at this writing -- and is likely to stay that way for the foreseeable future as other companies have thus far been slow to adopt Intel’s I/O technology.

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