A good safe guard is to always back up.
Video cards may die but that's no big deal same with the MB and ram but the HD is a different kettle of fish altogether.
Personally I see the life of a pc or laptop as 2 years max.
At the moment a i7 with Intel board.....1TB HD and 16GB of ram, and on board Intel video can be bought for under $600.
Just my 2c worth.
