Motherboard GIGABYTE GA-A75-D3H
Monitor Dell UltraSharp U2715H
Cable DVI BURO HDMI19 (m) - DVI-D(m)
in the review write that the resolution is more than FullHD works, that is Dual Link cable still
Windows 7х64, drivers video chipset, etc. — with of.site motherboard.
In the BIOS forcibly included Onboard Dual Link DVI, but the resolution is higher 2048х1152 does not work.
In the settings AMD scaling options are unavailable, they are superb and the image is stretched to full display resolution. Search of parameters of scaling and ITC nothing.
You must either remove the scaling so that the image was not full screen but fresh. Ideally, of course, include the full 2560x1440.
UPD1: setting UPnP monitor driver & utilities, DELL Display Manager yielded nothing.