question about HP tattoo on hard drive and motherboard?
 

I have a HP computer and I don't know why HP tries to this tattoo crap? I don't understand this tatto crap? Anyhow, If I replaced a hard drive only? Do I just tattoo only the hardrive? Do I run the HD dmi utility? 2 options on utility

1. Save DMI info on hard drive
OR
2. Erase DMI info on hard drive

So, basically I will run only the HD dmi CD and choose option 1.
If there is no mother board replaced. Then, I don't have to tattoo motherboard?

or Do both have to be done regardless if one is replaced or not?
Please, anyone who works for HP or have experience. Please, post your answer. Those of you who are PC Gurus can help me out please.
I appreciate your reply. thank you very much.

thanks :)