Hi CarsCerreta
I am Dave, an Independent Advisor, I will help you with this . . .
1
Check both ends of the cable that goes form your PC to that monitor to make sure it is connected correctly
2
Turn your PC off, wait a few seconds, then turn it on again, boot into BIOS, is that yellow line showing in BIOS, or is it just showing in Windows 10?
3
If that yellow line is also showing in BIOS, then it is not a Windows problem, it may be a loos connection or hardware problem
4
If that is just showing in Windows, then go to the support page for your PC on the manufacturers website, and form there, download and install the video card device driver they recommend . . .