Toshiba laptops are notorious for overheating, causing problems such as the system freezing up, the blue screen of death, or an actual automatic shut-down. Usually this problem is caused by dust trapped in the computer's heatsink, which prevents the cooling system from working properly. Solutions are fairly easy and straightforward.
Computer shops say that up to 20 percent of Toshiba laptops brought in for repair have issues with overheating. Symptoms may be as simple as the keyboard and bottom of the laptop being very hot while the computer is working, or the fans running at maximum rotation while the system becomes very slow for several minutes at a time. More inconvenient issues are common, such as the system completely seizing up and having to be "killed" with the battery pulled out, or the computer may shut down all by itself with no warning. Sometimes the laptop works fine until the user starts any significant memory-demanding applications, like photo editing software, several Internet windows being open at the same time, or an Internet video stream.
A common problem with the Toshiba laptop is that dust becomes clogged between the cooling fan and the heatsink, a device which lowers the temperature by dissipating heat into the surrounding air. Now heat produced by the processor is trapped inside the laptop, and the fan cannot blow it out.
If you or a friend know enough about computer hardware to take the case apart, you can clean the heatsink. Some Toshiba laptops allow access to the heatsink with a latch on the bottom of the case. You will need to remove the fan, then clean the fan and heatsink with a vacuum cleaner or a can of compressed air, specifically designed for computer cleaning. See the Resources section at the bottom for links to detailed instructions.
Sometimes the fan becomes defective and must be replaced. A common sign of this problem is the fan becomes noisy and perhaps makes a grinding sound. Again, a person handy with computer hardware will easily be able to replace the fan, which can be purchased directly from Toshiba.
A couple jerry-rig solutions can work, too, if the heatsink is not completely clogged. You can try putting a vacuum cleaner hose to the fan opening and see if that draws out enough debris to clear up the problem. If not, keeping a desk fan running, pointed at the back of the laptop, will keep the machine cooler. Also, laptops stay cooler when not sitting flat on a surface. Placing the laptop on a stand is a possible solution. You can buy or make a stand, and if you don't care about aesthetics, even two 9-inch-long pieces of wood or a baking rack will work.