Here are step-by-step instructions for taking apart a Toshiba Tecra 9100 laptop and removing the motherboard.
In a Tecra 9100 laptop some key components can be accessed from the bottom. In order to remove both memory modules, hard drive, DVD drive and Bluetooth moduele follow steps 1-3.
If you are using this guide for removing and replacing the laptop keyboard, simply follow steps 4-7, do not remove anything from the bottom.
After the top cover and display assembly is removed, as it explained in steps 3-11, you can access and clean the cooling fan.
By the way, in a Tecra 9100 the motherboard consists of two different boards. The I/O board shown in the step 17 and main board shown in the step 20. If your laptop suddenly lost sound and Wi-Fi connectivity at the same time, most likely there is a problem with the I/O board.