*BRUSH LAG? Read This...
Q,
Sorry i have been quite busy lately and just tried to read up on the thread. I did read your response and I'm thankful for you taking the time out to do a test.
I cant really add much in terms of a response other than I did a complete system reinstall recently and tried out CS3 vs CS4 again.
On default settings, CS4 was still horrible. It had the same exact performance issues as it did before doing a clean install of OS etc.
Anyways, i did read your message and decided it was a good time to try to compare CS3 vs CS4 again with your input in mind.
I was able to get CS4 to perform better by changing some OGL settings. I tried just about every combination of settings possible, and these did the trick.
I found that the best OpenGL performance came out of doing the following:
OpenGL - ON
Vsync - OFF
3D Interaction Acceleration - OFF
Force Bilinear Interpolation - OFF
Advanced Drawing - ON
Use for Image Display - OFF
Color Matching - ON
These settings helped with brush lag a lot. Doing the same "endless fast circular stroke" test that i asked you to do, I saw a lot less lag than with default opengl settings or any other configuration of opengl settings. HOWEVER... There was a slight lag and over time it did built up... but on the good side, it kept up fairly well and it is now useable. Now I know no one will likely do this kind of stroke often, but it helps to show the performance of the brush stroke. With the OGL settings i mentioned above, I was able to now draw with faster short strokes that many sketch artists are familiar with while gesturing a figure etc.
So those settings helped brush stroke performance. NOW... Its important to note that, with CS3 now on the same system, CS3 had absolutely ZERO lag. It was ridiculously smooth and still a lot better in every way BUT... atleast its now possible to draw a stroke in CS4 without it feeling "off" and annoying.
CS3 is virtually instant. With the same endless circular brush stroke test, CS3 keeps up perfectly and never lags.
To reiterate CS4 on default OGL settings had significant brush lag that made drawing impossible, painful and frustrating. With the above settings, It made it usable and pretty damn good... BUT still slower than CS3.
This was all tested on Quadcore QX6700, 8GB ram, Vista 64, GF 8800GTX at 2560x1600, full screen, intous3 tablet, etc.
I cant comment on any improved clone tool performance yet. (i havent given them a good run through on a photo). I was more concerned with brush performance because it was just in your face bad on default settings and all other variations of the OGL settings being on or off. I'll continue to compare and see what comes up, good bad or other wise.
I will also add this... I also tried overclocking the video card, and I did see some performance increase. Take that for what you will. It may be something to consider for those that are interested.
To all, i do recommend trying those settings to see if it improves your brush lag. It did in my case, but its still not as fast as CS3. CS3 is instant, while CS4 is now instant at very start of stroke and responsiveness retains fairly well for a moderate length stroke, but the longer it gets (fast strokes), a slight delay is present but it tends to keep up just behind your pointer. (Its just not instant like CS3). Its far better than it was at default settings, where from the very start, the stroke would draw on screen after you drew it.
With those OGL settings above, short quick strokes are now responsive enough to use. But i do have to stress that CS3 is still faster.
Q: also these were at 100% zoom. The zooming out performance increase was still there, but atleast now at 100% performance is better, dare i say usable.
Again i cant comment on the other issues cause i havent given them a run through yet.
CS4 with OpenGL off, was still slower than CS3.
If you have tried just about everything, including every combination of OpenGL settings in PS... try the ones above. I thought i had tried every combination with the best of my understanding of what i know of OpenGL... despite Adobe's poor descriptions of what these options actually do in PS... Anyways these settings helped greatly.