Breakthroughs and major achievements to the computer graphics experience in fact happen quite rarely. The last main incidence was a move to multi-GPU rendering: Crossfire, Dual GPU cards, and nVidia's SLI technique. A drawbacks using these technologies are pretty obvious. More than one motherboard is requisite for both Crossfire and SLI compositions, and dual GPU cards are prohibitively costly for all but the most hardcore enthusiasts. Another concern, clearly, is the fact that you end up consuming two cards worth of power more than one.
With regards to software, people end up with a decision: you can span a desktop across numerous screens, thereby running multiple applications across one or more displays, however, generally, spanning an application across above and beyond only one screen means that it could not be accelerated. So people ended up with a non-enviable choice: speed or size. Unfortunately, you couldn't have both.
Well, times have altered, my friends. AMD's Eyefinity technology is that subsequent plateau in mainstream, multi-monitor output. Eyefinity enables the user to have up to six screens controlled from one card, and thereby enabling a huge area of more than 24 megapixels. If you take a chance to read AMD’s literature on Eyefinity, it says that “we are inexorably on the road to the ‘holodeck’ (as conceptualized on Star Trek).” Given that the Star Trek holodeck had worked into it concrete feedback based on energy fields and such, this could be reaching a bit much at the moment, but none-the-less, the technology is certainly moving along.
Possessing Eyefinity, one video card can direct up to six screens, according to the type of the card, of course. AMD's view is that all 5000 series video cards will support Eyefinity. The trick here is that it falls to the graphics card manufacturer to make a judgment whether, and how, Eyefinity will be implemented on that particular card. As of September 2010, the time of this copy, only the ATI 5800 model line of video cards possess Eyefinity enabled in CrossFire mode. The HD 4000 string of cards, and all of their predecessors, don't bear the Eyefinity advances. As fantastic as that sequence of cards was, they simply do not have the horsepower, or the output connectivity for displays, needed to fuel more than two ultra resolution screens.
So, how do we get 3 displays running off of only one video card, what is this new DisplayPort we keep hearing about, and precisely why do we desire it? For a lot of years, Dual-Link DVI existed as the professional multi-monitor interface of choice, but that is about to alter. Being digital, DVI doesn't have the need of a digital-to-analog converter per monitor that VGA requires, it also does need that there be a devoted clock source for every single screen (this element is also accurate of HDMI). According to AMD, the signaling demands of DVI demands so many I/O pins from the video card that extending the monitor past two monitors was just impractical. Engineers recognized this at ATI back in 2004, and started working on some thoughts to eliminate and move beyond the DVI restrictions
So, do you need a DisplayPort connector so as to run EyeFinity? Will you need to acquire new screens? No, you will not. There are DisplayPort to DVI and also DisplayPort to VGA adapters, commonly called dongles. There are two different kinds of dongles for Eyefinity: passive and active. Much like any other variety of dongle for your notebook, these adapters adapt one type of connection into another form of connection. Conventional video port types are based on a technique named Transition Minimized Differential Signaling (TMDS) and use either DVI or HDMI interfaces. The problem here is that TMDS is almost completely different than DisplayPort. For just one example, TMDS brings to bear raster scanning, whereas DisplayPort is packetized. The protocols are pretty diverse. Also, the power specifications are openly diverse: TMDS typically runs at about 5V while DisplayPort is only 3.3V.
Passive dongles drive non-DisplayPort signals over the DisplayPort connectors by shifting signals from one configuration to the other. The graphics card is able to sense that a passive dongle is attached to the DP connector. At that point, instead of passing a 3.3V DisplayPort stream, the card outputs a 3.3V TMDS signal through that port and the passive dongle shifts the voltage level up to meet the TMDS spec.
Active dongles are made up of a DisplayPort receiver (which attaches to the graphics card) as well as a TMDS transmitter, which integrates a digital-to-analog converter (DAC) for VGA output. That’s genuinely the main difference between the two types. Power is commonly given by a cable that connects to a USB port. With an active dongle, the adapter looks like a DisplayPort to the graphics card, so the card transmits DisplayPort signals natively. Included in the passive situation, the card outputs TMDS for HDMI or DVI displays.
So the pimary thing to realize about Eyefinity and dongles is that there’s a hard limit of two TMDS output streams, period. There's no give here. So, if you want to employ Eyefinity to set up a 2x1 “array” (yes, dual-monitor Eyefinity seems a bit stupid, but that’s how the driver sees it), it doesn’t matter what you pitch at the card. Two VGA screens? No issue. You maybe could use a VGA adapter on a DVI port and an active VGA dongle on a DisplayPort connection. Just keep your legacy output stream count in mind as you scale beyond two screens. “If you’re already using two DVI connectors on the board, you can’t use a passive dongle because, in theory, that would be a third TMDS signal stream,” says Roger Quero, technical leader at AMD’s GPU Technologies unit. “You can have two passive dongles, and the rest have to be active. Just like, if you’re thinking about the six-output card, that’s six mini DisplayPorts. Two of those connections could be passive, putting out TMDS over those ports, then the rest have to be active so that we think it’s a DisplayPort screen.
Author Resource:-
Donald Fountain draws on over three decades of computer hardware and programming knowledge, managerial experience, and two Bachelor's Degrees, as well as six Associate's degrees for his writing. He is the founder and publisher of PlanetEyefinity.com, and DisplayPortMonitors.com, as well as a support supervisor for one of the largest web hosting firms in the nation.
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