It’s always a matter of isolation when diagnosing an intermittent problem with computers and components. Try to determine what you were doing immediately prior to the lines/stripes occurring. Try to replicate the conditions just prior to the lines/stripes appearing the first time. There can be multiple reasons for lines/stripes on your monitor. some of them  are: 1. Outdated drivers 2. Residual power in the monitor caused short-circuiting 3. Cables are damaged or incorrectly connected 4. Monitor refresh rate not synchronized  5. Video card issues Some potential thing to try: 1. Update your drivers  2. Disconnect all monitor cables, power off, unplug power, waits 1-5 minutes for power to drain, reconnect and try again 3. Check cables for damage and reseat 4. Adjust monitor refresh rate 5. Check video card, reseat in slot    
Tried BIST, it passed (issue could not be replicated).
"DS: Stripes/lines on screen, how to determine the cause?"