Be sure to see my new site MacPerformanceGuide.com.
Just added to DAP is my research on optimizing Photoshop performance on the Mac Pro (but the ideas should apply to PC users as well). I’ve researched the use of 8/12/16GB of memory, along with 1/2/3/4/5/6 drives RAID stripes for the scratch disk. There are very clear results here, along with some other tips and hints. I’ll be adding results for 32GB memory and the new Seagate 1.5TB hard drives soon as well.
If you’re working with large files that hit the scratch disk, you’ll definitely want to read this report (login required). If you don’t yet subscribe to DAP, here’s the short story: get 16GB memory and use striped RAID. The full multi-page report contains all the results, as well as how to set everything up, and why.
Update: a few hours after I published, a reader suggested using Bigger Tiles (wow!), and I discovered another trick as well—together good for an amazing 33% reduction in test time.