I have an Acer TimelineX 4820TG-6847, the other day while doing nothing but browsing the web the fan just kicked into full speed and CPU temps rose to 90c-100c. I checked and here are no processes putting load on the CPUs or using any system resources. The fan sounded like a really loud like a go kart+a baseball card in bike spokes. I shut the system down let it sit for a whole night then tried turning it back on, as soon as I turned it on I could hear the sound coming from the fan but it was very low, by the time I got to the Win7 login screen the fan was already at full speed and the temps were very high again and the laptop was very hot to the touch. I let it cool down again over night then turned it on and F2 into the bios and let it sit, it did the same thing, after maybe 10-20 seconds the fan was at full speed and the temps felt very hot to the touch. I took apart the laptop to check the cooling fan, there is one fan that cools both the cpu and gpu, I made sure the brackets on the heatsinks for both the CPU and GPU were tightened and cleaned all the dust and dirt from the fan vents, when I turned it on same thing, crazy loud fan and overheating. The fan seems to be spinning fine and blowing air from the vent, even though it is extremely hot and running at full speed. I noticed the area where the fan is around the Esc key is the hottest area followed by the middle of the keyboard(CPU) then the GPU around the lef Ctrl key. What could be causing these extremely hot temps and the fan running at full speed without even being logged into Win7? Any help would be appreciated. Thanks.