CPU Temp always stuck

[alexceltare2]

Hi, I'm new to the forum and I hope I will respect all the rules and start with my problem.
I've recently purchased a new CPU for my olde HP G70 laptop(yes, i know, but I got it free) from <Intel Core 2 Duo T5800 2.00GHz> to <Intel Core 2 Duo T9400 2.53GHz> and I was really happy with the new performance until I saw 2 problems:
1. The laptop shuts down suddenly when I play a fairly decent game, never happened before.
2.The CPU Temperature in <CPUID HWMonitor> always show the same value without changing. Only if I restart the laptop it will show a different value but it still hangs in there without any change. Everything else like Mobo, GPU, HDD fluctuates well.
The first problem is weird because before the CPU swap, the laptop went really hot(GPU:90*C, CPU: 57*C...) but all it happened was a lag in the game then everything went back to normal(I assume it has an automatic cooling down system) and with this CPU, the game runs well then at some point all shuts down. I guess is overheating but I can swear I haven't felt any hot air from the cooler.
The problem didn't came once I change the Processor power state capped at 85%. But then another problem, The CPU is capped at 1.59Ghz instead of 2.1hz because this new CPU has only 3 states: 800Mhz, 1.6Ghz and 2.53Ghz so is too much under-clocked.

So my question is:
- Why does the laptop resets at normal CPU speeds and before it didn't?
- Why is the temperature not changing?

Could it be because I didn't reinstalled Windows? Could it be because the thermo-paste? I clean the air vents recently. Thank you so much.

 

[Hamoodeh99]

you need to be sure that the laptop mobo fully supports the new cpu. the old one uses 65nm technology and the new one uses 45nm technology.

 

[alexceltare2]

you need to be sure that the laptop mobo fully supports the new cpu. the old one uses 65nm technology and the new one uses 45nm technology.

Yes. The manual stipulates that the T9400 is supported. That was the reason I picked this CPU and not a Quad Core.

 

[alexceltare2]

Don't worry guys, i solved my problem. Apparently the CPU can't refresh the temperatures constantly for I don't know what reason but the sudden shut down was a big problem. So what i did was to carefully take all my laptop apart again and grind/polish with sandpaper the pads where the cooler touches the processor die resulting in a pristine clean surface. Also, the thermopaste was spread evenly on all the flat surface thus maximizing the contact. So to sum it up, it is important to carefully apply paste and make sure the thermal conductive metal is clean for a better cooling.

UPDATE! My freaking laptop still shuts down after some point in the game. Darn it! All is to do left is to buy a laptop cooler but I ain't gonna buy that because I sit on my bed and to the work most of the time. So yeah, Temp not refreshing, laptop shuts down unexpectedly even after a little game of Heroes 5.