Dual monitor with ATI 5870

[rentrimillos]

I need help! I installed Ubuntu 12.04 and everything runs fine with one exception.....my dual monitor setup. I even got my scanner and webcam working! I have an Asus VW266H plugged into HDMI and an Asus VE256 plugged into DVI port. My video card is an AMD/ATI 5870.

Using the display setup, I can have one monitor or the other monitor on, but not both.
These are the messages I get:
requested position/size for CRTC 147 is outside the allowed limit: position=(1920, 0), size=(800, 600), maximum=(1920, 1920)

and:
GDBus.Error:org.gtk.GDBus.UnmappedGError.Quark._gn ome_2drr_2derror_2dquark.Code3: requested position/size for CRTC 147 is outside the allowed limit: position=(1920, 0), size=(800, 600), maximum=(1920, 1920)

I don't know where to start. Can anyone help, please?
Thanks

[T.J.]

Hello! =)

Please forgive my manners in answering a question with another, but before I can help you, I need to know:

1. What interface are you using? The default named "Unity"?

2. Did you install the proprietary ATI driver from Additional Drivers?If you have, you may find this (http://ubuntuforums.org/showthread.php?t=1810936) useful.

3. Do you have a second DVI port?

Thanks!
T.J.

[rentrimillos]

Thanks TJ for trying to help....no apology needed.

I did install the ATI driver, but no success.
Also, I need change a statement I made....the second display is connected thru the display port, not DVI. I apologize for that misstatement.
I assume that I am using the default interface....I didn't change anything.
How do I determine which interface I am using?

TJ, thanks again.

[rentrimillos]

TJ

Sorry....I am using Unity

[QIII]

Are you using the Catalyst Control Center in admin mode to make changes?

[rentrimillos]

QIII

How do I verify that I am doing it in admin mode?

Thanks for your help

[QIII]

Are you being asked for a password?

[rentrimillos]

QIII

Thanks....that took care of my problem.
I was able to resolve it when I logged in as admin.

Everything works!
Thanks all