What is causing thin white diagonal lines on my CRT

I am trying to determinie if it is my CRT reaching EOL or if my video card is going bad. I have a dual monitor setup using a NVIDIA QUADRO FX 1300 video card. Both CRTs have a series of thin white/gray diagonal lines across both screens when I boot up. They stay even after my system has started windows and applications have started although they are much less visible.

 

If you've tried the CRT's on a different PC, and the lines remain, then either you're approaching EOL or the bright/contrast (usually bright) is too high. I had a Sony that did exactly what you described: even w/ the bright turned down to zero, it had the lines... then it died after about 2 months....

hopperdave2000

 

If you boot to Safe Mode so the system is only running in standard VGA mode do you still get the lines?

If not then it is possibly a driver problem but if so then I'd start to worry about the CRT. But also check the connection between the PC and the monitor in case the cable has been pulled out slightly and is giving a poor connection on one or more pins.