Cannot install Windows 7 on an Intel Pentium 4 HT Prescott PC

One of my relatives still runs XP on his machine (which is capable of running Windows 7, the CPU is newer than the one on my Dell). I told him that I will try to upgrade (clean install) his machine to Windows 7. Although gool ol' 7 is going to die in ~2 years, he is going to still have 1-1,5 years worth of upgrades and security fixes.

However, something unexpected happened. When I tried to boot from USB, I got a BCD error (Just for reference, I used Rufus to create the bootable USB). I tried using a CD, but the BIOS does not want to cooperate. When I try to change the boot settings in order to make the CD drive the 1st option, it changes the 2nd option to Removable device, rather than the hard drive. Also, when I try to boot from an existing installation on another hard drive, I get a blue screen.

Parameters: 0x0000007B (0x80D86B58, 0xC0000034, 0x00000000, 0x000000000)

Comparison between my specs and his specs (CPU to be exact):

Intel Pentium 4 Northwood @ 2,40 GHz (pins on processor) // Intel Pentium 4 HT (Hyper-thread) Prescott @ 2 GHz (pins on socket, socket is LGA775)

My older Dell can handle Windows 7 Starter just fine. I installed it 2-3 times without any issues.

Does anyone have any ideas as to why this happens? I'm open to any suggestions.

Windows does not like being booted from removable devices!

Did you select the 'Standard Windows installation' in Rufus? With this method it should install Windows 7 on the PC's hard drive. In any case, the problem will have nothing to do with the hardware of your relative's PC, but with the way you try to install it.