Should I replace my thermaltake mini copper orb???

[chopstxxx]

I have a 1.33 t-bird @ 1.47 (10.5 x 140) and use the mini copper orb hsf. My cpu temp is 39.9 and my case temp is 24.1 degrees right now and hits low 40's(cpu) during the day. Will a new HSF improve my temps significantly? If so can anyone recommend a relatively quiet(no deltas) and cheap(under 30 dollars) solution? Thanks in advance

 

[chopstxxx]

chopstxxx

 

[Wind]

If u r at tht temp...just leave it. Why waste $$ on a better HSF when under 40C id already good?