Fuzzy Blurryness on computer monitor screen

[bwisdom]

I use a crt KDS usa monitor and when i was at 60 hertz on refresh i had flickering,fluzzy, and blurry lines on screen. The lines aren't that annoying but it is noticable. I've switched it to the highest refresh rate which is 85 hertz, but it didnt last as long as 60 hertz. Right now im using 72 hertz and so far it hasn't shown any of those lines. Any ideas? suggestions? I use a XFX Nvidia 6800 gt 256 mb. I built this computer and got it about 2 months ago. When I used dxdiag in the run i tested direct draw and direct 3d it seems that some pixels are outa shape, but when i changed the refresh it became better.

 

[CJJohnson]

Blurry and unstable picture can sometimes be down to the monitors power supply failing. How old is the CRT?

 

[bwisdom]

2 years

 

[CJJohnson]

See if you can borrow a different monitor just to see how that looks.