Monitor going dark intermittently

[tetromino]

I wonder if anyone here has heard of such a problem....

My monitor (Viewsonic p95f+, a 19inch CRT) has been intermittently going dark. Once every 20-30 minutes or so, the monitor would go dark for about quarter of a second (actually, it's almost like a dark wave moving down the monitor) and then returns to normal. One time I saw the darkening process take a few seconds, but usually it's almost instantaneous -- it looks as if the monitor blinks once.

The problem with diagnosis-by-replacing-hardware technique is that the darkening is very irregular. Some days it darkens every 20 minutes. Sometimes, for several days or even a week it would work with no darkening at all.

My question is what could be causing this.

The monitor? (about 2 years old, perfect picture quality)
The cables? (sitting tight)
The video card? (geforce 4200 128M, not overheating AFAIK)
The drivers? (nvidia-kernel-1.0.6629-r3)
X? (xorg-x11-6.8.2, but I had also experienced the darkenings with 6.8.0)

Any ideas?

[palsyboy]

I doubt this really helps at all, but I had at least a similar, if not the same, problem with SuSE 9.1 on two different machines. Both were using Gateway VX900T monitors. Both worked fine when I switched to Gentoo.

Just wanted to let you know that you're not alone, and, if it's the same thing as I had, your monitor's not broken.