few tips:

1. Operate the laptop in a ventilated environment i.e., do not keep it on your lap or on a bed/matrress. Keep it on a table and also make sure there is nothing blocking the fan outlet.

2. in addition to 1., you may also use a laptop tray which has its own fan (available at jarir, carrefour etc)

3. Motherboard replacement is definately expensive and it makes more sense to buy a new laptop. However, the chipset on the motherboard can be repaired. the repair machine looks something like this (http://www.alibaba.com/showroom/motherboard-chip-repairing-machine.html). Not sure if it is available in Doha so you may have to find a repair shop back in your country or in Dubai. if you find a chipset repair shop in Doha, let me know as well :)My laptop has the same problem

Consider if your laptop atleast 1.5 or 2 years old, has the battery gone through 500+ recharges. Search vendor forums e.g., toshiba forum and look for such information, for some models it is specified e.g., after 500 recharges battery life is over etc.... It's all subjective, you have to search for the relevant sutff.