usb drive - Getting an error on Live USB boot: "(initramfs) Unable to find a medium containing a live file system"

There are plenty of threads on this topic, I've tried every solution mentioned there:

1. Different version of Ubuntu (Kubuntu 13.10, Kubuntu 12.04, Ubuntu 12.04)


2. Using USB 2.0 and USB 3.0 ports


3. Different Live USB creation software (Linux Live USB Creator, unetbootin, Universal USB Installer, Kubuntu Startup Disk Creator)


4. Switching from IDE to ACHI


5. UEFI and legacy boot


6. Disabling secure boot.


7. Replacing "quiet splash" with "nomodeset" in GRUB



8. Plugging out hard disk


9. Using different USB drives (regular USB stick, external USB HDD)

But I still get the same error every time. No difference.

My PC is a brand new computer, all systems are functioning well (I tried to install Windows 8, it works just fine).

• Motherboard: GA-970A-DS3P



• CPU: AMD Phenom II X4 970


• Graphic adaptor: AMD Radeon HD 5770 (Vapor-X)

What to try next?
Please help me prove to my husband that Ubuntu can be installed everywhere, I am out of ideas.