well if you want to keep your data, dont kill the hard drive and remove it after the motherboard dies.
I accidentally, for real, and I'm a techie.....killed a motherboard and then 2 days later my daughter dropped another pc and killed that motherboard simply by dropping it (it wasn't securely on a table, desk or floor because I was working on it).
Anyway, the way I killed my motherboard was to remove the processor and put it back in wrong and the dang pens bent.
You could try to "find out the specs of your motherboard", then accidentally put the processor in wrong and bend some pins.
I really wouldn't suggest this method of getting a new computer because you will waste a lot of good parts. Depending on the type of computer, I could use a motherboard so if you decide to ruin something else, like the memory, hard drive, on board stuff by accidental scratching, keep me in mind for the other parts ;)
You may want to see a marriage counselor afterwards because this isn't healthy to be sneaky