I'm not sure what you mean by monitor has fuzz.
Do you mean the screen is fuzzy?
Is it out of focus?
This is rarely caused by a cable.
The CRTs get old and images get poor.
Replacements from third party or from Haas are available.
If working on your own, it is the old IBM Monochrome MDA standard.
Also what do you mean by newer monitor.
Is that different than what the machine had new?