I purchased this Laptop a couple years back, had to replace the hard drive with one under the warranty, that is all. The laptop started having overheating issues about 6 months after I bought it, was never bad. Since then, it gets worse and worse and worse. I work on laptops for a living, so I have taken the thing completely apart, down to pieces, cleaned and put back together. It resides in the far left corner, under the power cord plugin, which is the video card. Hense, the reason why it gets hotter when watching Youtube and what not. Right now it has been on for about half hour, according to Speedfan the GPU temp is 85C, about 10 minutes ago it reached 111C. I do have a laptop cooling system for it, however when using that and watching a video, it still sits around 90C. Any, and I mean, any suggestions, I am willing to try. Please do not respond with the typical, try cleaning suggestion or the "stay away from AMD", blah blah.
When my laptop started acting up (heat - fan died), it actually took 4 reassemblies before I finally got the TIM right. I can only suggest replacing the thermal pads and reapplying new thermal compound. It is possible also that the fan itself has become weaker in pressure and needs replacing. Check to see that you feel heat from the exhaust (without cooler) from about 3"
I did find this "mod" for heat but it is a real mod if you want to go that route http://www.youtube.com/watch?v=8X6Im9L8fmw
although the video is not the greatest, the mod does look intriguing