Hey there... hoping someone smarter than me can help

I have a XFX HD-587A-CNF9 Radeon HD 5870 graphics card, that I used to run 1600x1200 on my old monitor. I just bought a Dell U2713HM who's native resolution is 2560x1440. However, in control panel, I can only pick 1920x1080 as my max-resolution.

Trying to figure out why I can't pick a higher option... 

I'm running Win7-64bit and just installed the latest Catalyst drivers (non-beta) and dell drivers. I'm connected using a DVI cable. 

Do I need a display port cable to get the max-resolution, or is this a dell-driver issue and the monitor isn't reporting all its' modes correctly?

Under Catalyst Control Center | My Flat Panels | Properties, it shows that dell monitor as max-reported resolution of 1920x1080@75hz. 

More driver-details:

Dell Monitor Driver:

Vesion 1.0.0.0, Date: 4/3/2012

Graphics Card Drivers - HD 5800:

AMD driver version 9.12.0.0, date 12/19/2012

BIOS Version: 012.020.000.002

BIOS Date: 2010/03/08

Thats an eyefinity 6 card. You are probably going to need a mini displayport to display port. 

I'd shoot XFX an email to see if any of those mini displayports on the back of them are powered for resolutions higher then 1920x1080 ( I think two of them are if memory serves but they may not be) 

Otherwise more then likely going to need a USB powered mini displayport > display port adapter.

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The supplied DP -> DVI dongle is only single link instead of the needed dual link. Just use Display port.

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awesome - thanks for the DisplayPort suggestion guys - i'll get a cable and see if it helps.

display port cable worked a charm - all good! thanks guys