Questions about temps

E4500 OCD to 2.65 passively cooled by ninja; idle low 30's load low 60's
EVGA 9600SC stock clocks: idle high 50's load low 80's
4gb PC5400 RAM
2 optical drives and 2 harddrives
Asus P5KPL-VM (X31)

All neatly tucked in a mini P180 case. 200mm top fan on low and 120mm rear fan on low no other fans other than the PSU fan which is isolated.

I use ntune to monitor the temps for gpu and fan speed is set at 13.85%. When gaming or wathcing a Bluray should the gpu fan speed up as the load increases. I think it may speed up a little bit. Don't hear any difference in sound. I am a little worried because my old 8600gt DDR2 only had a like a 7 degrees diffenrece between idle and load 56 and 63 respectively. I am trying to keep the system as quiet as possible. So my next step would be to add another 120mm fan like a 500 or 800 rpm scythe on the lower HD bay to provide extra airflow.