Tired of struggling with big (500 MB) scan files in PS CS3 with my system, I recently purchased a new computer (i7, 12GB RAM, Vista 64-bit, ATI 4850 512MB video card); I also downloaded the trial version of PS CS4. Well I was as happy as can be, what took 5 min. on my previous system now took 20 sec. Then, quite suddenly, I noticed some odd behavior: painting on a mask, I saw the effect appear somewhat delayed and not the area I had painted! Then I noticed a delay in turning layer visibility on and off. Upon clicking on the eyeball, the eyeball remained for a few seconds, then disappeared but no effect on the image, i.e. the layer was still visible unless I used the mouse wheel to resize. There were some other processes slowed as well. Although I was working on a 1.5GB file at the time, smaller files behave in a similar way. I removed and reinstalled the video drivers, the BIOS and CS4, none had an effect. Interestingly, if I launch CS4 in 32 bit mode, it behaves normally, but defeats the purpose of having all that RAM. I checked the Adobe forums and could not find a similar report.
Anyone have a suggestion?