To measure performance under Photoshop CS4 we turn to the Retouch Artists’ Speed Test. The test does basic photo editing; there are a couple of color space conversions, many layer creations, color curve adjustment, image and canvas size adjustment, unsharp mask, and finally a gaussian blur performed on the entire image.
The whole process is timed and thanks to the use of Intel's X25-M SSD as our test bed hard drive, performance is far more predictable than back when we used to test on mechanical disks.
Time is reported in seconds and the lower numbers mean better performance. The test is multithreaded and can hit all four cores in a quad-core machine.

Photoshop performance is actually very good on these chips, the extra cores help make them faster than even a Phenom II X3 720. For $99 you're getting better Photoshop performance than even more expensive dual core processors.
The Pentium E6300 isn't competitive here, despite being Intel's closest priced processor. The Q8200 is faster than both of these options, but it's also more expensive. Again, AMD priced the 620 on point.
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