Grey410, what temperatures does it read in the BIOS? Idel temps of 40C plus with C2D's are rarely heard of. Especially sicne you are using a Z9500!
I've got my E6300 at 3.2 Ghz and it idles at 32C... I do remember reading that the ASUS temperature sensor is around 8 - 10 degrees (Celcius) off though. I'm pretty sure that's the reason.
Feel the HSF. If it feels hot, then yeah, it's around 45 - 50C. If it's cool / partially warm, it's around 25 - 30C (what it should be).
EDIT:
Download the Intel Thermal Analysis Tool from here:
http://shintai.ambition.cz/files/tat.exe Tell me your readings.
EDIT 2:
Also, you should be doing Prime95 tests to check stability.