Update 1 (Sept 19, 2016) : I have fixed my CPU fan issue, I have copied the post about it in the main thread, but do read the posts, a lot of gem in there.
EDIT: My GPU fans work perfectly, and never had speed dip or slow ramp up. It keeps the gpu under 75C all time, and under 90C with +250 +300 OC.
I have a P650SG (Eurocom), and I have been having this weird CPU Fan problem for a long time...
The CPU Fan would suddenly stop for no apparent reason (i can hear the fan just suddenly went silent), and it will take around 1-2 second to restart and ramp up to top speed really slow...
Also it react to the temp change really really slow... the CPU would jump to 97 degree and throttle, then the fan speed will slowly increase....
Here is the Idle and Load test graph:
In the graph you can see the CPU fan ramp up rather slow, and it have a 4000->0rpm dip when I switched fan profile in Clover Control Center, and a 4000->1000rpm dip when I stopped the benchmark...(it shows dip to 1000rpm, but i think it dipped to 0rpm from what the fan sounds like)
I have tried different BIOS and EC, 1.03.04 to 1.05.01, non helped. Right now I'm on Premamod v2, it is not improved.
This is really bizarre to me... I don't know what is causing this problem, I did an RMA with eurocom but their inspection shows no problem with the cpu fan... Is the cpu fan failing? or is the power delivery failing? PWM failing? I have no clue now...
Please someone point me to the right direction...
UPDATE1: I have fixed this problem. Just an update in case anyone else have the same problem in the future, this CPU fan problem is because my CPU fan is failing, and also the cooling module is not that good. This is actually quite common, Clevo have a new version of CPU cooling module in P651SG.
I bought the newest version of CPU cooling module for P651SG on taobao, changed it on with the 5583 thermal paste(this thing is so much better than my Arctic Silver 5 or MX4), and the problem is gone. The new fan even sounds less aggressive at 100% fan speed.
Temp has been very good, stay below 85.
I also bought the custom cooling pipe that connect CPU heatsink to GPU heatsink, it is said to lower CPU temps more since the GPU fan will help a little. I didn't bother putting it on since temp is very much improved already. I bought the CPU cooling module for about 40 USD, and the heatpipe 10 bucks, way lower than the quoted price of around 50 CAD for only the fan + 30 bucks shipping I did a couple weeks ago with eurocom.
BTW some pic after I changed the CPu cooling module, broken case corner, and applied vinyl skin.
I want to open up the laptop and clean out the fans and/or change the thermal paste. The cpu (i7 4720hq) temps hit the high 90s when running any kind of games and I am a little concerned. I haven't been able to find any videos or guides to take out the heat sink/fan.