This conversation has been merged. Please reference the main conversation: Lightroom: LR4.2 Performance Issues remain
i have imported a small number of raw photos from a canon mark 2 - about 2000 photos. when i try to view the pictures to grade them, i can see the first 10 or so as quickly as i want, but after that, lightroom starts slowing down and saying "Loading...". The number that i can see quickly varies. Ihave set the preview to 1:1, have optimized my catalog several times.
This is a very fast computer with the c drive split across 2 SSDs. the 1 tb drive I am using to hold the photos is not an ssd drive. it is about half empty. Because of the way my computer was set up, some user data is not on the c drive where adobe expects it and apparently this prevents adobe bridge and photoshop from running unless i run as admin, but this does not seem to be an issue for lightroom.