Dual monitors have become so common these days, they’re cliché – and we can’t have that! So Jared went for the gold and purchased a third QNIX QX2710 Evolution II. Getting two QX2710s to work in harmony is hard enough, but three? That’s pure madness!

Background

The QNIX QX2710 Evolution II monitors present an excellent value. These monitors use Samsung PLS panels, an advanced S-IPS type LCD, for excellent color reproduction at all viewing angles. Imported from South Korea, they rival competitors that cost in excess of three times as much. The 27″ screen also boasts an amazing resolution of 2560×1440, giving users huge amounts of screen real estate. So what’s the catch? Well, the stand leaves a lot to be desired and there’s a distinct lack of inputs. In fact, there’s only a single input to be found – a dual-link DVI port, required due to the high resolution (single-link DVI only supports resolutions up to 1920×1200@60 Hz). Most high-end graphics cards have at-least one dual-link DVI output, making it trivial to support a lone QX2710.

Dual QX2710s are a different story. While high-end nVidia cards often have dual dual-link DVI outputs, AMD (or ATI…) cards generally only have a single dual-link DVI port (note – DVI-D is DVI-Digital, NOT dual-link). Jared had the misfortune of owning an AMD Radeon 7870, with only a single dual-link DVI port, plus a displayport, HDMI, and a single-link DVI port. (Jared would like to point out that the 7870 is a fantastic video card and the “misfortune” here is only the lack of a second dual-link DVI port.) I discovered a (glitchy) solution to running the QX2710 over single-link DVI, giving us dual monitors on AMD/ATI graphics cards.

Triple-head, Attempt I

In the absence of an available dual-link DVI port, three solutions are available (ordered from least preferable to most preferable)

1. Single-link DVI or HDMI w/pixel patcher
2. DisplayPort to HDMI adapter + HDMI -> DVI cable
3. DisplayPort to Dual-link DVI adapter
4. Buy a video card with more dual-link DVI ports onboard

For Jared’s first attempt, we drove one QX2710 over dual-link DVI, the second one with a DisplayPort to HDMI adapter in conjunction with an HDMI to DVI cable, and the third with another HDMI to DVI cable with the pixel patcher installed. While this worked,  there were several drawbacks. First, the pixel patcher appeared to cause problems with hardware accelerated video; some youtube videos would only show a black box where the video should have been. This was remedied by disabling hardware acceleration in the web browser and flash. Next, Team Fortress would refuse to work on his computer after the pixel patcher was installed. Finally, because the pixel patcher allows the DVI port to run faster than the official specification, very high quality cables must be used for it to work properly. Even then, an element of luck is still present – the QX2710 must be able to handle the higher clock rate and the video card must also handle the higher clock rate without error. Unfortunately, Jared’s setup was not perfect and his patched monitor would occasionally artifact; because the DisplayPort to HDMI solution works similarly to the pixel patcher, that monitor would occasionally artifact too. For those wishing to overclock their monitors, neither the pixel patcher nor the DisplayPort to HDMI adapter are acceptable solutions.

Triple-head, Attempt II

Jared’s second attempt at a triple-head setup combined options 2 & 4. He purchased a powerful Sapphire Tri-X AMD R9 290X graphics card that includes two dual-link DVI ports. The Sapphire Tri-X R9 290X is a state-of-the-art graphics card that includes a factory overclocked 28nm GPU with 2816 stream processors, 4 gigabytes of onboard GDDR5 graphics memory, and over 320 GB/second memory bandwidth. What’s important is that the 290X has enough umph to power the three 2560 x 1440 QNIX displays, for a total display area of 7680 x 1440 pixels.

For this attempt, we attached two of the QX2710s to the Sapphire R9 290X with dual-link DVI cables. The third QX2710 needed an alternate solution, so we used the DisplayPort to HDMI adapter, followed by a high quality HDMI to DVI cable. This allowed all three monitors to be used without the pixel patch. Naturally the two native dual-link DVI QX2710s are perfect, however, the third QX2710 occasionally exhibits light artifacting. For the most part, this artifacting is able to be resolved by cycling the power – that is, turning the monitor off and on. We think the occasional inconvenience is worth the $70 in savings.