They're nearly the same, however the 925 will come with a better heatsink.
IMO, the 925 would be the better buy.
Do you plan on overclocking?
What other cards (if any) will you be adding in?
I guess i wont overclock initially, im fairly new to that sort of thing, though i hear its pretty simple. I think i will most likely overclock later on (a year or so).
As far as other cards, other than the graphics card, i may add a tv tuner, but not really anything else.