I have an ASUS EAH4850 TOP/HTDI/512M Radeon HD 4850 512MB 256-bit video card[/url] running in Windows 7 x64, and I cannot get my second 2560x1440 monitor set to run always at maximum resolution. This card has two dual-link DVI-I ports. Both monitors are connected via a dual-link DVI-D cable, which are Monoprice Product ID 10489 27" models. The ATI Catalyst software and/or Windows selections only allow 2560x1440 on one monitor (DVI port 1) and 1920x1080 on the second (DVI port 2). I've swapped monitors between the ports to assure that each monitor is properly functioning and can physically attain the 2560x1440 resolution display. I am using the latest driver for the ATI Radeon HD 4800 series, version 8.970.100.1100, dated 4/29/2013. Also, it seems that running both monitors simultaneously IS physically possible. I have some 3Planesoft 3D screensavers, which when set to have a duplicated display on both monitors, WILL display the real-time 3D renders at the maximum resolution on both monitors. I've done extensive searching in the forums and on the Internet and have yet to find something that fixes the 2nd monitor resolution issue. Most (or all) posts describe using one dual-link DVI-D port and some other graphics port, whereas I am using two dual-link ports. I've tried the registry hacks to add 2560x1440 resolution at the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class and HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Video locations. I've tried enabling and disabling GPU scaling. I have not yet tried creating a custom EDID, as I don't think that's the issue. Can anyone help?