You mentioned Photoshop. Do you use Lightroom for cataloging things?
If so, definitely go for that smallish SSD for the OS and put the lightroom database on it also.
And I second whats been said about getting a i5.
my desktop is i5-2500 (3.3ghz) /120GBSSD/2TBHD/16GBRAM/Radeon HD7800 2GB and it runs anything I've wanted, including new games.
(except for some work-related items that need insane amounts of RAM)
I paid $400 US for it used a year ago, when it was a year old. I expect similar specs should easily fit in your budget now as New.