What you describe sounds like problems with the latest display drivers.
The driver version numbers you're listing are not accurate. 2012's drivers all start with 12, those in 2013 will start with 13, etc.
12.8 is the most recent version that works acceptably well with Photoshop. If you installed 12.10 or one of the newer betas, you will have to have UNinstalled it first, then you would have had to reinstall 12.8. It's important to make sure enough of 12.10 has been removed from your system to ensure 12.8 will work properly.
If you work with their tech support folks, ATI / AMD themselves propose a method for fully uninstalling a version of their driver to ensure it's been fully removed that includes a run of something like Driver Sweeper to clean out remnants their own uninstaller misses.
Myself, I've found that simply uninstalling 12.10 or 12.11 using its own uninstall facility seems to have been enough, but I wouldn't bet that that's true for every system.
Beyond that, try the different advanced modes in the Photoshop Edit - Preferences - Performance - Advanced GPU dialog (e.g., try Normal or Basic), making sure to restart Photoshop after each change.
Though it seems pertinent, it's really not consequential whether a system worked with Photoshop CS5. The newer version makes more demands of the GPU because more functionality has been migrated to the GPU.
In summary, I use 12.8 (with a Radeon HD 7850), and I have found it to be reasonably stable and functional. I suspect that because of the path you took to get to where you are you may have a combination of two driver releases installed.
I THOUGHT I had 12.10 completely uninstalled and 12.8 back on. But I'll go see if I can find the process to make absolutely SURE I have all of 12.10 gone so I can get 12.8 back on... I looked in the Catalyst Control Center, but and I'd SWEAR last week it said the version was 12.8, but I just checked again and it now says 12.10 again... So, I'll go make sure it ALL goes away this time...
I didn't think about it too much, but after going back to 12.8, LR stopped having fits and worked fairly well. Last weekend LR suddenly started acting wonky again and slowing down, but I figured since I'd gone back to 12.8 it was something else. Now I find out I'm back to 12.10...
Once I get all the driver stupidity straightened out, do you have any recommendations for optimizing the PS preferences? Is there a topic or file or document somewhere that'll help me optimize so if I DO get anymore bizarre behavior I'll know it's not my settings?
Not sure you'll need to do much... I have everything GPU-oriented turned on to the max; the Catalyst 12.8 driver seems to support it all.
Seems to me there's an auto-update checkbox somewhere in the Catalyst control panel pages. You might want to make sure that's unchecked.
If you want to describe your computer system in general, I can potentially make some general recommendations (e.g., what to set RAM limits to, etc.).
OK, as near as I can tell I've now gotten rid of EVERYTHING from 12.10, and things are back to 12.8. when I check in the Catalyst Control Center, it SAYS it's using version 12.8 of the software... And I found the "check updates" and shut it off....
The current system is an ASUS P6T motherboard with an i7 920 quad-core running at 3.8GHz. I've got 12GB of DDR3 memory, and an ATI 5770 1GB video card. O/S is Windows 7, 64-bit Professional. I've got 5 internal SATA spindles, all 7200 RPM.
C has my O/S and applications on it.
P is a 1TB spindle that contains my .dng files
Q is a 1TB spindle set as a scratch disk
T is a 1TB spindle set as a scratch disk
Camera Raw Cache is a 60GB partition on the Q spindle
In Photoshop, I've got preferences set to
Automatically Save Recovery every 5 minutes
Available RAM: 10986 MB
Ideal Range: 6042-7909 MB
Currently I let Photoshop Use 8459 MB (77%)
History states is 200
Cache Levels: 8
Cache Tile Size: 1024K
In Advanced Graphics Processor Settings
Drawing Mode: Advanced
Use Graphics Processor to Accelerate is checked
Anti-alias Guides and Paths is checked
Use OpenCL is NOT checked
30 Bit Display is NOT checked
I'm not sure if there's any other preference that's relevant, but let me know if you need any other info...
Are the original "glitchy display" issues you reported gone? I assume so but you didn't actually say.
For what it's worth, even though I don't personally have monitors that can handle 30 bit data, I have checked the 30 bit display setting. Somehow it seems to me something ended up working better when I did that.
A History States value of 200 is arguably a bit high for a system with only 12GB of RAM. It can contribute to swapping a lot of data to scratch when you've been running Photoshop for a long session.
Speaking of scratch, I don't think there's any advantage to having two separate 1 TB scratch disks. If that's all you're using them for now, you could potentially boost performance by combining the two into a single 2 TB RAID 0 volume, which will essentially add the drive speeds for large data transfers. I would suggest against partitioning the disks at all, as it will virtually ensure seeking if things are accessed from both partitions simultaneously, and seeking is bad for performance.
The rest of the settings I think you have set pretty well.
Have you tried setting the Advanced Setting for "Drawing Mode" to "Basic" and restarting Photoshop?
I gave LR and Photoshop a quick start and tried a couple of the things that intermittently failed. They worked fine, but I'll have to give things a much more stringent workout before I can tell... Unfortunately, I'm trying to prove a negative, so if it doesn't happen it could be 'cause it's fixed, or it could be that I just haven't done whatever I did before that caused the problem. I'll know more in a few days.
I'll turn on the 30-bit data just to see if it changes anything.
As far as the scratch disks... They're both used for other things. Q has my ORIGINAL .NEF files on it, and there's probably 200 GB available. T is a backup disk that gets used at 2 a.m. when I back up my images. It has 200 - 300GB available. So, both are used for other things and I wanted to be sure there was plenty of room for the scratch files.
I'll try turning down the number of history states, to maybe 150, although my system INSISTS the Photoshop is always 100% efficient...
I'll stop back later in the week when I've got some better information on bizarreness...
I haven't tried setting it to basic... What is the effect of changing from advanced to basid for the drawing mode?
I beleive it just changes some API calls. It shouldn't affect image quality or performance.
I've now been using LR and PS for the last 3 days with the 12.8 ATI drivers instead of the 12.10 drivers... And, I know you can't prove a negative, BUT SO FAR the bizarre behaviors I was seeing are gone. I can zoom, create guides, and do normal stuff without any problems. PS is still using every bit of memory I give it, but so far it's still saying it's100% efficient.
The change back to the old driver ALSO helped some of the performance problems I was seeing in Lightroom...
SO FAR, SO GOOD......
That's excellent news, right in keeping with what I've seen.