Old HP Media Center m7000 desktop

Anyone have a kid who is into tinkering with old PC's? I have a 20yr+ old dusty desktop. Pulled it from storage, still boots up, but hard drive died so pulled it out. So comes with no hard drive or monitor, but can give a ps2 mouse and kb... Used to run a security system for a store. BIOS is giving a fan error but still boots past it. Not suitable for modern computing needs but could be useful for learning about old hardware or tinkering. If you throw an old hdd in there and install an OS it should still function. Let me know Pickup only