outdated hardware?

[mfenn]

I built it myself 2 years ago...

If you built it yourself, you must have installed Windows at least once, right? If so, just do the same thing that you did before, only make sure to delete all the partitions near the beginning of Windows Setup.

 

[vailr]

All 3 popups in your screenshot appear to be malware.
Run these:
Junkware Removal Tool
http://www.majorgeeks.com/files/details/junkware_removal_tool.html
Malwarebytes:
http://www.majorgeeks.com/files/details/malwarebytes_anti_malware.html