Should I keep this configuration?

[salz]

I just ordered a 80-120mm fan adapter and put a 120mm Panaflo fan that pushes 103 CFM on my heatsink. I can't say much about the adapter and improving CPU temps., because when I had the fan running at full speed, the CPU temps didn't change much at all from when I had an 80mm fan. However, my case temps did improve from 40-41 degrees while using the 80mm CPU fan, to about 36 degrees while using the adapter and the 120mm fan. The problem was that running the 120mm fan was a little loud, so I plugged the 120mm fan into the "Fans Only" connector so that the fan received less power. After playing counter-strike for about 20 minutes, my CPU temp. was 55 degrees and my case temp. was 36 degrees (I restarted my computer right after playing the game and looked at the hardware monitor in my BIOS). The great thing about this setup is that my computer is almost silent. I have four case fans and one 120mm CPU fan all running less than full power (is it 7 volts when it's only the black and yellow wire?) and the interference that I hear from my speakers is louder. My question is about my CPU temp. When I had the 80mm fan my CPU temp. was around 50-52 degrees, but my case temp. was around 40 degrees. Now with the 120mm fan my CPU temp will go up to about 55 degrees, but my case temp. won't break 36 degrees. I'm using an AMD Athlon 1800+ CPU. What do you think? I'm bringing this computer to college, so I want it to be quiet, and I don't plan on doing any overclocking. Have I finally found the right configuration?