Ok I did everything again, checked the cooling fan, is clean. Check the heatsink grill, clean. Cleaned and re-applied thin coat of grease and put the heatsink back tightening the screws in order and a little bit at a time. Turn the computer on and still the cooling fan is full speed, stopped for half a second and is still on full speed.
Here are the readings from MobileMeter:
Frequency: 266Mhz
Temperature: 85.5C
Charge Rate: 0.00w
HDD #0: 28C
The HDD started at 24C and keeps going up, Im not using the cooling pad right now.
Frequency changes to 200Mhz, 233Mhz and 266Mhz.
Here are temps from Speedfan, just in case they can show something:
HD0: 28C
Temp1: 86C
DIMM: 255C
CPU: 85C
GPU: 255C
EDIT: updating as the HDD #0 temp in MobileMeter is at 30C now, again the fan is still full speed and I'm not using the cooling pad.
What's up with all these readings? 266mhz for the CPU? Something is definitely not right. I don't know about the GPU and Dimm readings, but the CPU is normally read accurately by Mobilmeter. I've never seen a processor trottle down that much, but its probably doing it because of the temperature. It's also probably why your videos are playing so lousy. Your computer must be running very slow overall.
If you boot your machine to bios and leave it there, will the fan still run at full speed? Also, please look in bios and check what the CPU frequency reads. To get to bios, continually press the F2 key directly after you boot up until you get an indication bios is loading. It also may be the F1, or F10, key... I haven't checked your model to find out what the right key is.
Also, if you can, find the bios screen that allows you to reset the bios to default settings. You can also reset the bios by removing the bios battery (or battery connector) and leaving it disconnected for about 10 minutes or so, then reinserting it... that is if it's not soldered to the motherboard.
This definitely looks like a hardware problem, but try resetting the bios first.