I processed a bunch of dark frames from my 5D and 10D as follows.
Viewfinder covered, lens cap on
ambient air temperature 68 F
RAW files opened in C1 LE 3.7,
noise suppression set to Low, banding suppression off
color noise suppression: Manual, set to 0
sharpening method : standard look amount 50 threshold 5
saved as jpeg high
reduced to 1200 pixels wide and saved as jpeg medium quality , no sharpening, using "process multiple files" in PS Elements 4