Booting To A Windows 8.1 Install Usb Drive

Computer is an HP Pavilion a6040n. It uses legacy boot, not UEFI.

I am trying to boot to a windows 8.1 usb drive. USB drive should be bootable, as I am pretty sure that I have used this same drive that way in the past and I have not changed anything. Also, it's bootable for MBR.

When the monitor first comes on, there are 3 options (which are nicely indicated on the screen for a few seconds, thanks HP).
esc - boot menu
F10 - setup
F11 - system recovery

I have tried pressing esc and pressing F10.

Sometime I have been able to get to a menu that lets me select which device to boot to. When I choose USB, the computer still boots to SSD.

Another time I pressed F10 and completely removed the hard drive from the list of boot devices. However, the computer still boots using the SSD.

I do see that I can install the OS by booting into windows and then running the setup file from the USB drive. However, I severely dislike that it doesn't wipe the drive clean, but simply moves the old install files to a folder as part of the new installation.

I suppose that one option is to format the partition on the SSD that I want to install to. However, I can't get my DVD drive opened to boot to my Linux system rescue cd (DVD drive occasionally malfunctions by refusing to open). As an aside, it's annoying that you can't open DVD drives quickly right when you turn on the computer.

 

Edit: to clarify the above post, pressing esc brings me to the menu that allows me to select which device to boot to.

 

Here is what the boot menu in the bios looks like (got to this by pressing F10):

Boot Device Priority
1st Boot Device: Floppy Group
2nd Boot Device: CD-ROM Group
3rd Boot Device: HDD Group
4th Boot Device: Network Boot Group

Floppy Group Boot Priority: Not Installed
CD-ROM Group Boot Priority: Not Installed
HDD Group Boot Priority: WDC WDS250G1B
Network Group Boot Priority: Not Installed

 

How do you select USB when there's no USB device in the list of options?

 

When I press esc, instead of pressing F10, it brings me to another menu. That menu lets me select which device to boot to.

 

List the devices on that menu.

 

Some older version of computer does not have USB in boot priority menu. You could just use . Use this simple technic to solve your problem.
Just download the zip file in item 2 from the link. Find the iso file in the extraction. Just use nero or imgburn to write to the cd drive , a new one.
Then change the boot priority to cd drive in your pc.
Then insert the cd and power on the computer.
The computer would boot from cd drive, making a display of menus at the top of the screen.
Use the arrow to select the usb from the list of menu.
Then you will find that usb will boot the OS , if it is bootable.
There are some conditions to make a usb bootable and i hope you would have done that.
Enjoy. The link is
https://www.plop.at/en/bootmanager/plpbt.bin.html