Samsung laptop overheating

Dear all,
I have a Samsung RF511 Laptop. Recently it started to heat up. It's quite strange but although the laptop heats up a lot, fan doesn't seem to bother to speed up.First I thought the problem is with the fan and cleaned the fan using compressed air. The problem persisted. Then I replaced the thermal paste and the laptop still heats up until 90 degrees. What might cause this problem? I check the temperatures with Speccy and it shows very high values, however fan just doesn't speed up. What might cause this problem?
Thank you very much in advance.

Have you checked the battery to make sure it isn't the cause of the over heating? When they start to go, or have a defect, they can cause overheating. Which, if not addressed, can fry a few things on the device.

Also, you should check if it is overheating only when used and plugged in via power cord. If so, you may need to replace the cord.

Depending on how old the device is, and if it is under warranty or not, will determine where to go from there. If it is under warranty, then you should be contacting the manufacturer about the issue. If it isn't, then there are a few diagnostic programs that will give you a much better idea of what is causing the problem. Personally I like "SpeedFan". http/www.almico.com/speedfan.php It is simple, and free, yet gives good information.

Have you checked the battery to make sure it isn't the cause of the over heating? When they start to go, or have a defect, they can cause overheating. Which, if not addressed, can fry a few things on the device.

Also, you should check if it is overheating only when used and plugged in via power cord. If so, you may need to replace the cord.

Depending on how old the device is, and if it is under warranty or not, will determine where to go from there. If it is under warranty, then you should be contacting the manufacturer about the issue. If it isn't, then there are a few diagnostic programs that will give you a much better idea of what is causing the problem. Personally I like "SpeedFan". http/www.almico.com/speedfan.php It is simple, and free, yet gives good information.