I rarely see the problem on my Mac Pro with two monitors, the secondary is my ancient 23" and the primary is the Apple 30"--I have noticed the odd slowness in replacing the generic application icons with the normal icon when opening the Applications folder for the first time after a restart. Subsequent openings are fine, as is switching the view from my normal default of List to Icon. Also a newly installed program gets the generic icon for the longest time, sometimes it stays generic until after a restart. And I use the new resize slider all the time for browsing graphics files. I also have lots of folders with custom icons, many graphics files with the Photoshop custom thumbs, not to mention some graphic files where I have created a custom thumb using an Applescript, and others where I have used a new Snow Leopard Automator Service to add a thumb. I even have a few things with custom icns files. I do sometimes see blurry icons for files with custom thumbnails in CoverFlow and Icon view, where the slider is set very high, and have surmised that is because Finder can draw much larger icons for files without thumbs, since custom thumbs are smaller (as in 128 pixels). When a file has a custom thumb, Finder displays it, and that small size is scaled up, to bad effect. Simply removing the custom thumbs and letting Finder draw something instead fixes the problem. I have not tinkered with any program icons, they remain whatever they are, and aside from tardiness in drawing them, they have always displayed fine.
I don't know what the cause might be for those who are having a problem, although bad caches might indeed be a likely suspect. One thing to try is restart and hold down the Shift key to disable third party goodies (and some of Apple's as well) and flush a number of caches. Try running for awhile in Safe Mode if you can (depends on whether something you depend on requires a startup item to be loaded) and see if the problem manifests itself. Then restart normally and see how it goes. I haven't tried a Safe Boot in Snow Leopard, but I would think it ought to still work. It's worth try.
Francine
Francine
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