Can I get back Original OS if hard drive was reformatted? & how? [ Edited ]

[The_Regal_Lady]

Can I get back Original OS if hard drive was reformatted ? & how?  (I was told, Factory O/S stays with motherboard...Is this true?

I bought second-hand. Auto-Detection found HP Pavillion (Model: np220aa) (Serial Number:[Personal Information Removed]) (P/N: 513430-002)

HPPHENOM x64

PROBLEM IS: previous owner wiped out hard drive, left no (windows.old)  file, Installed Win 7 U;timate (which I love BUT....MS saying "is not Genuine")  I really cannot afford new license, want to roll back to Vista but don't even know What Version, type or Product Key would be.

Someone said this info Stays burned into hard drive.....Please How do I find if this is true? 

[CherylG]

The only info on the hdd is the OS installed on it now ,unless you still have the D:\Recovery partition? There is some hope if it is there.

The Vista version and license key should be on a sticker attached to the side or top of the machine.

Probably the best option is to order Recovery Media from your models page HERE  Or,phone HP to request a Recovery  set.Usually less than $20 and will restore back to original, with no license key needed.>>Contact HP

[The_Regal_Lady]

Thank you Cheryl for the quick response. Ok, I actually found the version and license key, it had been removed and reattached inside the case. Now I am wondering..."Will any Vista Recovery cd's work as long as I use the correct license key? and do I need to do anything special or difficult or do the recovery disks self install when loaded?  Really don't want to mess this up. Oh, and  Does windows 7 have to be removed first?

[CherylG]

Recovery Disks will format the hdd removing Win 7 first. However, Recovery Disks from another model aren't likely to work. The process checks for info in the BIOS chip on motherboard to see if Recovery matches hardware. I have seen a few cases where two models could use the same set, but they were manufactured during the same quarter.

If you have a  plain Vista dvd of the same version indicated on the case sticker it should work. Boot with it and choose 'Custom" installation to completely remove Win 7 first. The guide HERE shows the process.

[CherylG]

If you prefer to stay with Windows 7, you can get an OEM copy pretty reasonable at Tigerdirect:

http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=5213932&CatId=306