Hello syukri,
.ISO is not available to download for bundled Operating system,
If you are planning to perform recovery on the unit, and if there is Recovery drive available on unit, you may refer to below link for performing Recovery through F11.
http://support.hp.com/us-en/document/c01867418#AbT1
And in order to get the Recovery media for your unit.
Kindly contact hp technical support :
Contact HP Worldwide
http://www8.hp.com/us/en/contact-hp/ww-contact-us.html
I hope that answers your question.
I am an HP employee, the opinions expressed here are my personal opinions, not of HP.
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