If you are wondering regarding Fedora or Linux specific advice (hardware compatibility), just search the hardware section of the forum and take note of the problematic (that is: to be avoided) components.
Generally speaking:
- buy a huge (aluminum) case: you won't regret having more space in it...
- buy a brand PSU (with modular cables, maybe)
- don't use the "stock" heatsink that comes with the CPU - buy a real cooler for your precious processor

- consider some hard disk cooling device
- an UPS is a good idea
- search for dvd burners and motherboards whose firmware is upgradable natively with linux
... and have fun