When requesting assistance, please provide the complete model name and product number (p/n) of the HP computer in question. HP/Compaq makes thousands of models of computers. Without this information it may be difficult or impossible to assist you in resolving your issue.
The above requested information can be found on the bottom of your computer, inside the battery compartment or on the startup BIOS screen. Please see How Do I Find My Model Number or Product Number? for more assistance locating this information. DO NOT include your serial number. Please enter the model/product information into HP's Online Consumer Support page and post it here for our review.
What you want to do isn't a "downgrade", it is just installing a different version of Windows. You will need to purchase a new copy of Windows 7 with a valid Microsoft COA and product key. The Windows 8 key is encrypted and embedded in the BIOS/CMOS of your computer, and is only valid with an OEM copy of Windows 8.
You may encounter numerous issues installing Windows 7 on your computer. There are BIOS settings that may have to be changed. You have to boot the computer with the correct media for it to recognize the current hard drive partition type. You may issues locating all the needed drivers. There may also be other issues.
HP doesn't recommend the installation of Windows 7 on a computer shipped with Windows 8, nor will it support the installation of Windows 7. HP will not provide Windows 7 drivers and suitable drivers may not be available for the hardware in the computer. Also, Windows 7 may not support some of the hardware or software features designed for the computer.
Make sure you create your HP Recovery Discs or USB Flash Recovery media before modifying or changing ANYTHING.
You will need to DISABLE "Secure Boot" and ENABLE "Legacy Support" in the "BIOS Secure Boot configuration" page on the settings page shown below, before you can attempt to install Windows 7;
or
Additionally, as the hard drive may be partitioned as GPT, you may have to boot the computer using the "UEFI - CD/DVD drive" or "UEFI - USB Flash drive" options in the "F9" boot menu. If "UEFI - CD/DVD drive", "UEFI - USB Flash drive" or something to that effect doesn't exist in the boot menu, please post a screen shot and/or descibe the listed boot options.
I suggest using Windows 7 SP1 for the best intallation experience. If you need Windows SP1, please see "How to Install Windows 7 Without the Disc" to download and create your own Windows 7 SP1 disc. If the DVD refuses to boot as UEFI, you may need to use a USB Flash drive (may require DISABLING "Fast Boot" and/or setting "USB 3.0" to "AUTO" in the BIOS) as the installation media. Please download the Windows 7 USB/DVD download tool to create a Windows 7 SP1 USB Flash drive. Please note that some computers may not recognize a valid UEFI enabled USB Flash drive if it is formated as NTFS and may require a FAT32 formatted USB Flash drive. You should be able to make a FAT32 formatted Windows 7 installation USB Flash drive using Rufus, UNetbootin, Universal USB Installer, or WiNToBootic. I like Rufus, as it has options for "GPT partition scheme for UEFI computer" and "FAT32".
If you have any further questions, please don't hesitate to ask.
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