Those are lower clock speeds than I typically run, so you should be safe with the heat, and the score is pretty good too. My best is listed below. My CPU score was around mid 700's I believe.
All things considered, these vanilla 7800's are pretty nice, especially when I can run Call of Duty 2 at 1280x1XXX resolution, full smoke effects and 4x's AA with no slowdown.
So, yeah, that score's pretty good. Not GTX class, but good nonetheless.