Acer pc wont load

The beep is a high pitch beep doesnt sound bad to me or abnormal. Checked the hd on another pc to try and load and got an error code pxe-mof...

If you need anymore info let me know

Ive tried entering bios but not sure really where to go from there in the acer pc, i took the hard drive out and tried to boot from an older pc (emachines) but wouldnt boot from there came up with the error pxe-mof. I'm not worried about losing the data on the hard drive there isnt anything really on there. However, i wanted to keep/recover the windows 10 os because i do not have a backup or disc amd would still like to use it as mu main boot drive. Also, i tried to put my other hard drive (older,smaller) into the newer pc but also couldnt boot. Im not sure how to enter safe mode on an acer desktop but i will look it up once i can. Could i try to recover a partion, or maybe migrating the wondows 7 os to the new hdd? Im not sure what to do, or what the problem is. Could it be the mother board? It does beep on boot so mother board should be good right?