Question Monitor shows static, faint horizontal lines when playing games, but okay when booting up ?

Oct 23, 2021
My old monitor has some horizontal faint grey lines, its like old tv trying to reach the signal.
I use the monitor as 2nd monitor to my laptop using VGA to VGA cable i also tried using VGA to HDMI adapter. But issue still persist

The weird case I noticed

  1. The monitor is clear when trying to boot up, but the grey lines start appearing after the windows login show up
  2. Grey lines always start crazy (makes weird up and down moves) when I use Max performance options from battery consumption
  3. When playing games, the faint lines also gone crazy, (up and down moves and more lines) but still playable, but its annoying
  4. weird effect when I do scroll up and down
its weird, I can some sort of controlling the lines by messing with power options xD and the faint lines making weird movement when playing games but my laptop monitor is okay only cracked lcd but not gray lines and blurry, straight broken. but maybe from the laptop itself?

the fact that the monitor is okay when booting up, (but the grey lines still appear if i restart the laptop)
monitor ViewSonic VA1931 WMA , i tried to google this product its weird enough that i don't see this product on their official websites with exact model name. :/

I also tried
  1. uninstalling the drivers both onboard and integrated gpu
  2. changing the cable, with/without the adapter
  3. trying different refresh rate & resolution
  4. wiggling the cable, nothing change
  5. google and tried their suggestions
maybe somebody can help, i think its electrical interference kind of thing, but that thing i don't really understand how to resolve it.