I installed two 120 mm fans to replace the single 80 mm fan that cools the upper coils of our frige [outside] They made a huge difference in how fast it pulls down initially and doesn't make but a fraction of the whine the OEM 80 mm did.
Tried the inside fan, but doesn't do any good if you have a "loaded" refrigerator. Anything between the little fan and the fins, blocks the flow of air.
I have a drip pan just below the fins of my frige that will not allow an upward flow of air.
2013 Silverado 2500 HD Duramax/Allison Tuned
Aviator Wright Flyer #1919
"First In, Last Out". 11B4Y
DAV, MOPH, VFW, 5/7 Cav,1/8 Cav Assoc.
11th ABN Pathfinder Co. N7MIP