U2713HM displayport link failure

Greetings.

I have a problem with connecting Dell U2713HM monitors to my unbranded PC.

The monitors fail to communicate by display port. Windows reports a displayport link failure.

Dell parts: 3 U2713HM monitors

My PC: Unbranded Intel i7 PC

Intel i72600k CPU Gskill 16 Gig RAM ASUS Z68 Pro motherboard Gigabyte AMD 7950 3 gig GPU, 2 installed. Ports available: 2 mini display ports, 1 HDMI, 1 DVI dual link per card. OCZ 128 gig SSD Hitachi 2TB 7200 rpm HDD

Relevant software: Windows 7 Ultimate, 64 bit AMD display drivers 12.10 AMD catalyst suite 12.10 Monitor drivers from CD supplied with U2713HM

Connections tested: mini displayport (PC) to fullsized displayport (U2713HM) HDMI to HDMI DVI dual link (supplied with monitor) Apple active mini displayport to dual link DVI-D adapter

Connection test results: HDMI connection works on all 3 monitors at standard 1080p resolutions. HDMI is unsuitable as it does not support full resolutions. DVI dual link works with all 3 monitors, but only 2 monitors can be connected at once as there is only 1 DVI dual link port available per card. Using DVI dual links is not possible in Eyefinity as all connections must be from the primary graphics card. The Apple active mini displayport to dual link DVI works with with 2 other monitors connected by DVI dual link, provided full resolution desktops across all 3 monitors, but since connections are not on the primary card, Eyefinity is not possible. Mini displayport to full sized displayport directly from PC to monitor does not work. Windows reports displayport link failure on all 3 monitors, on several different cables.

Conclusions: The GPU displayports are functioning normally or the Apply adapter would also produce a negative outcome. Eyefinity should be possible using this method by using 1 DVI dual link cable and 2 Apple active mini display port to dual link DVI adapters, however these units are expensive due to their niche market position. Passive adapters are unsuitable as higher resolutions are not supported. The Dell monitors appear to be unable to connect using the native displayport interface. All other connections on the monitors appear to be working normally.

Question: Is there a solution to ensure the U2713HM is able to accept a connection on the native displayport, or is my only solution to buy an expensive active adapter unit from a third party?

Edit: I tried to turn audio power save mode off, but the option isn't even available when the monitors are connected by dual link DVI. It's greyed out.