When OpenGL stopped working (option greyed out)

Question

I discovered a weird bug in Photoshop 12.1 x64 with nVidia graphic cards and what´s causing it:
Problem (on all off my PCs):   OpenGL support in prefs / performance is greyed out, no shadow below open documents visible ( == OpenGL not working).  After deleting prefs.psp and restarting (as the www says), OpenGL support was working again, on next restart: no support - option greyed out again.
Solution: if deleting the prefs file or the whole prefs folder don´t work, check if you have a custom workspace with the brush floating panel open.
If so, close it and remvoe it from workspace, restart PS and.... OpenGL support is working again!
I could reproduce this bug on all of my PCs, no matter what type of GFXcard and driver version is installed.
Maybe that bug occurs only with Win7 x64, PS 12.1 x64 and nVidia cards, but removing the brush panel solved it on every machine!!
I´ve opened a support ticket and provided Adobe with screenshots of the working and not-working states... maybe they can fix this with an update!
This are my system specs for the tested machines:
workstation 1:
Intel i7 980X HexaCore (with SMT)
ASUSP6T7 WS Supercomputer
6 x 4GB DDR3 triple channel
nVidia Quadro CX
3x WD SATAII HDDs
dual monitor
Wacom Intuos4 XL
3Dconnexion SpaceExplorer
contour Shuttle Pro2
workstation 2:
Intel i7 975 Extreme Quadcore (with SMT)
ASUS P6T Deluxe V2
6 x 2 GB DDR3 triple channel
nVidia GTX 580
2x WD SATA HDD
both systems running on:
Windows 7 x64
Mastercollection CS5.5
latest updates for OS, CS5.5 and GFX drivers...
Maybe this threat helps .... ;-)

Answer 1

I did heavy testing the last days including systems at my home and at a friends office.
In fact, I can´t tell, what´s causing this, but it seems to depent on a certain type of installation. But first the tested systems:
nVidia GTX480 SLI, Win 7 x64, CS5.5 - working
nVidia GTX580 Win7, CS5 - working
ATI HD4870x2, Win7 x64, CS5 - working
nVidia GTX580, Win 7 x64, CS5.5 (update from CS4 ->CS5 -> CS5.5) - not working
nVidia GT240M, Win7 x64, CS5.5 - working
ATI X1900XT - XP SP3 x64, CS5 - working
nVidia QuadroCX, Win 7 x64, CS5.5 (update from CS4 ->CS5 -> CS5.5) - not working
ATI HD4390, XP x64 SP3, CS5.5 (update from CS4 ->CS5 -> CS5.5) - not working
nVidia GTX480, Win 7 x64, CS5.5 - working
On each system I installed the latest driver & updates, rebooted it and followed the same procedure:
1 - removed (==renamed) prefs folder
2 - start PS
3 - open prefs / performace
4 - config OpenGL for "Advanced"
5 - closing prefs and restarting PS
6 - checking OpenGL when active: pt7
7 - Open menu "Window" and and select "Brush" (or press F5)
8 - docking Brush-panel from original position to the tools-panel on the left
9 - saving workspace as "BrushTest"
10 - restarting PS
11 checking OpenGL
Since you have all older Versions still installed when you update i.e from CS4 to CS5 I tried this with every installed version.
On my two office WS I have CS4, 5 and 5.5.
After trying this with the GTX580 with this results: CS4 working, CS5 working, CS5.5 not working - I today started PS 12.1 for working and saw that tiny shadow below the document - WITH the brush panel open!!
Checked it and now its working proper. I have no clue what has changed over night but it did it...
My primary WS with the Quadro card still refuses to actived OpenGL with the opend brush-panel, no matter what I try.... maybe I gonna deinstall that CS4 to 5.5 mess and get me another license for the full CS5.5 instead of the update from the update...