my alienware M17xR3 is too hot!

hello,

i have a problem with my alienware M17xR3: the 4 cores are too hot

1) in idle, the temp of the 4 cores is 70°C  (instead of 45°C)

2) in full load, the temp of the 4 cores is above 90°C (instead of around 70°C)

3) the fan speed whatever is very low. (the speed doesn't change whatever the utilization of the cpu). i don't ear the fan always

4) there is always a cpu multiplier underclock to down the temp under 90°C (according the intel 2630qm specs)

what is the problem?

have you an idea?

thanks