Windows 10: Is my motherboard or CPU malfunctioning

My Windows 10 computer had worked fine for over a year. Then one day I came home to my computer in BIOS. If I completely turn off the computer and turn it back on, I get the diagnosing PC message then it tells me that Start Repair could not fix the computer. If I reboot without turning the PC off, the computer boots to straight to BIOS.All my hard drives are recognized in BIOS. I've tried every repair method I could from the USB bootup media and other things I have found on the net from using diskpart to trying to rebuild the MRB. I just get error messages, saying the drive is write protected.

:)

 

[FS][US] CPU, NForce4 skt 754 motherboard (with PCI-express slot, rare!), DDR RAM

bump, CPU's stepping is now listed.

 

Upgrading Motherboard and CPU

I bought a default Lenovo K450 a few years back that came with Windows 8 preinstalled. Well over the past few months I've upgraded the PSU, GPU, and moved too an SSD without much of a hassle since I was using the same motherboard and CPU. Well, I'm moving
too a whole new upgrade and changing the case, motherboard, CPU, and adding a network card. My question is, once I've changed out all of the parts, will I need to reinstall Windows 8, or can I just install Windows 10 again like normal and follow the steps
with customer support to establish the legitimacy of my previous Windows OS? I have the OEM and Product Key.

 

Choice of memory and motherboard... a bit stuck...

No one who got some suggestions on this one, huh?

I've found out that the Asus M3A78-T needs to be flashed, so then that motherboard is excluded from my list. Which motherboard and memory should I then go for? Any suggestions?