It sounds like Neat Image is the problem, if the raw file is processed with ACR or DPP and there were no 'sparkles'. ISO 640 image should not be that noisy unless there is a camera issue or gross underexposure. Did you try the NR in ACR and get the same results ? I think Adobe has really improved the NR in their products recently.
|Morning At Picture Lake by Buzz Lightyear|
from Dawns first rays
|AT-6 Harvard by jarud|
from Trainer aircraft
|Matterhorn by ewng|