How can I stop my computer from shutting itself down?

Stanna wiped her old computer and reinstalled Windows XP with dual partitions. Now, it just shuts down on its own. Leo says that it's likely a hardware problem, potentially a power supply. If she's getting beeps when she turns it back on, that's a "post code," and the number of beeps tells her what the problem is. Just search the number of beeps on Google. Given the age of the computer, it's probably time to get a new one. She could pay to have it fixed, but at that age, it's not really worth it.