PS CS5.5 No Longer Detects GPU

Question

On 9-4-2012, I was given a brand new Dell at work. At about 1pm on 9-12-2012, I noticed scrubby zoom had stopped working. I checked Preferences>Performance>GPU Settings, and I’m told the graphics acceleration is unavailable. I found that very strange, as I had been using said acceleration for over a week.
I've spent several hours searching for a solution, but found nothing that even remotely addresses both my problem and circumstance.
I'm not an idiot, I've been using Photoshop since 1998 and I've been building computers as a side business since 2001. I don’t have a giant magnet sitting next to my computer, and said computer isn’t resting in 3 inches of water. There are no tin foil covered Honey Badgers running amok inside my computer case.
Yes, I have rebooted my computer.
Yes, all my video/device drivers are up to date.
Yes, Windows is up to do date.
Yes, all Adobe products are up to date.
Yes, all my Adobe products are legit.
Yes, the GPU features worked fine for 6.5 full business days before dying.
Yes, I fiddled with Nvidia Control Panel settings while trying to fix this issue.
Yes, my video card (Nvidia Quadro 600) is official supported by Adobe…
http://helpx.adobe.com/photoshop/kb/tested-video-cards-photoshop-cs5.html
No, I’m not using any third party plug-in’s
No, I have no cheap off brand nonsense installed or plugged into this computer. It’s exactly how Dell shipped it, but with Adobe CS5.5.
I’ve attached a screen cap showing my specs and that all my drivers are up to date.
Let me just reiterate. At 11am this feature was working fine. At 1 pm it was not. I did nothing to this machine between that time, other than reboot Photoshop. And please, no "Buy a Mac" responces. Don't you think I'd have one if my company was willing to buy me one?

Answer 1

Chris Cox wrote:
And you can run the sniffer manually to see what it might be running into (it's a small command line program).
First I've heard of that.  That would be the program sniffer_gpu.exe in the Photoshop CS6 installation area?
I take it one can test the 64 bit GPU driver by running the 64 bit version, and the 32 bit driver by running the 32 bit version.
Output's a bit cryptic, but maybe if something were wrong it would be better...
C:\TEMP>"C:\Program Files\Adobe\Adobe Photoshop CS6 (64 Bit)\sniffer_gpu.exe"
Device: 0000000000270B68 has video RAM(MB): 1724
Device: 0000000000270B68 has video RAM(MB): 1024
Vendor string:    ATI Technologies Inc.
Renderer string:  ATI Radeon HD 5670
Version string:   3.0.11762 Compatibility Profile Context
OpenGL version as determined by Extensionator...
OpenGL Version 3.0
Has NPOT support: TRUE
Has Framebuffer Object Extension support: TRUE
OpenGL ok
OpenCL ok, version=1.2 AMD-APP (938.2)
Return code: 3
C:\TEMP>"C:\Program Files (x86)\Adobe\Adobe Photoshop CS6\sniffer_gpu.exe"
Device: 005E5F74 has video RAM(MB): 0
Device: 005E5F74 has video RAM(MB): 1024
Vendor string:    ATI Technologies Inc.
Renderer string:  ATI Radeon HD 5670
Version string:   3.0.11762 Compatibility Profile Context
OpenGL version as determined by Extensionator...
OpenGL Version 3.0
Has NPOT support: TRUE
Has Framebuffer Object Extension support: TRUE
OpenGL ok
Return code: 1
-Noel