I've been having a tough time trying to discover the cause of this issue I'm having with a computer at my job.  I did a fresh load of Windows to a new SSD that was purchased to upgrade a Dell Precision T1500 from a WD Blue HDD that was previously installed.  I had no isses with the previous load.

Here is the format in the sticky:

Graphics Card
- Visiontek ATI FirePro v4800 (figured out that I was dead wrong on the mfg)

AMD Catalyst Driver Version, and Driver History
- Initially FirePro 8.982.8.1 – uninstalled via Programs and Features when first discovering “Unable to save display settings” error

- FirePro 8.911.3.4 – same symptom, used Trexxy DriverFusion 1.3 to completely remove all traces of driver.  Remants remained at “HKLM\Software\Microsoft\Windows\Current Version\Setup\Pnplockdownfiles”, “HKLM\System\ControlSet001\Enum\Root\LEGACY_AMDKMDAG”, “HKLM\System\ControlSet002\Enum\Root\LEGACY_AMDKMDAG”, and “HKLM\System\CurrentControlSet\Enum\Root\LEGACY_AMDKMDAG” due to permissions.

- FirePro 8.911.3.1 - same symptom, used Trexxy DriverFusion 1.3 to completely remove all traces of driver.  Remants remained at “HKLM\Software\Microsoft\Windows\Current Version\Setup\Pnplockdownfiles”, “HKLM\System\ControlSet001\Enum\Root\LEGACY_AMDKMDAG”, “HKLM\System\ControlSet002\Enum\Root\LEGACY_AMDKMDAG”, and “HKLM\System\CurrentControlSet\Enum\Root\LEGACY_AMDKMDAG” due to permissions.  Modified permissions so that they could be accessible to “administrators” and ran DriverFusion again to remove all traces of the driver.
- FirePro 8.85.7.3 – same symptom, decided to post on this topic instead of trying other steps.

Operating System
- Windows 7 Professional 64-bit Service Pack 1
- Was working under prior load of Windows 7 Professional 64-bit Service Pack 1; OS was reinstalled to utilize new SSD.  Old HDD with prior setup still works fine.

Issue Details
- Only two monitors can be enabled at once, third monitor is listed as being disconnected.  Any two will function, but a third will produce the error in the Windows Screen Resolution settings of “Unable to save display settings” when trying to extend desktop to third monitor or clone third monitor with one of the existing monitors.  AMD Catalyst software does not give option to enable all 3 screens.


Motherboard or System Make & Model
- Dell Precision T1500

Power Supply
- Dell Precision T1500 PSU

Display Device(s) and Connection(s) Used
- Acer H233H Connected to DVI port

- 2x Dell ST2420L’s connected via DVI to display port adapters

- BizLink BZL-KS10009(B) active display port adapters

- DVI-I Single Link cables being used
- include specifics about any cables, adapters, splitters, hubs, used

CPU Details
- Intel Core i7 870

Motherboard BIOS Version
- Dell Precision T1500 2.3.0 BIOS

System Memory Type & Amount
- 4x “Hynix 2GB 1Rx8 PC3 10600U-9-10-A0”

Additional Hardware
- Crucial V4 256GB SSD, CD/DVD Burner

Additional Details
- Looked at these web resources to try to discover solution on my own (most issues did not specifically apply to the issue I was having):

http://en.community.dell.com/support-forums/desktop/f/3515/p/19382353/19883398.aspx

http://superuser.com/questions/473293/ati-firepro-v4800-3-monitor-support

http://boardreader.com/thread/ATI_Firepro_v4800_5mejzXbio0n.html

http://www.overclockers.com/forums/showthread.php?t=702829

http://www.craftiscranium.com/2012/04/solved-unable-to-save-display-settings.html

http://ma.wishmesh.com/2010/04/ati-eyefinity-with-3-monitors-unable-to-save-display-settings/

http://www.tomshardware.com/forum/335458-33-getting-monitors-work

http://www.heathpost.com/2011/09/tech-note-three-monitors-on-ati-firepro.html

http://popthestash.com/2011/12/15/193/

Kind of a strange one I know...  I'm kind of surprised that no one even has a suggestion?

I resolved this issue.  It was driver related.  I installed the old HDD and made a note of the driver that was installed, which was 8.83.5.4.

I used Trexxy to remove driver 8.0.11.3.1 (the most recent driver available for the card from the Dell website), modified the registry keys so I could completely remove all the traces that were detected, then restarted and installed FirePro 8.83.5.4 which allowed me to enable that third display.