Physical memory Dump after mounting an external hard drive

Any help that you could offer me please! This is actually the problem of my friend about his PC when he mounted an external hard drive into it. When the command window asked him to restart the PC, he restarted it. During the booting process, the following error message appeared “0x000000F4 (0x00000003, 0x8A56ABE0, 0x8A56AD54,0x80604418) PERFORMING PHYSICAL MEMORY DUMP.”
And so I presumed that the problem is in the internal memory of the computer. Then, I opened the chassis of the system unit and mounted out the two RAMs and installed it again. I restarted the PC, but the same error had been displaying. I bought a new RAM and replaced the old RAM that the PC have, but it didn’t work fine.
Any help will be greatly appreciated.
