Vostro 1500 and the unruly external monitor; a modern plight

I bought a Vostro 1500 (GF8600GT). It was good.
I bought an Acer AL2016W 20" Widescreen LCD. It took some doing to get working, but it was good.

Two months down the road, the external monitor has started to flicker to black at seeming random, with escalating frequency as I keep it turned on. I'm pretty unhappy with this :/

So I'm sort of playing the elimination game. No change has occurred; I installed a Vista-recommended "driver" for the external monitor after the problems started, but they had no effect and I removed them. I've checked all cabling, and fiddled with refresh rates and Geforce drivers. This only occurs with the external monitor, never the laptop monitor. It occurs more frequently in graphic applications (games, 3d applications, photoshop) than bog-standard Windows.

Upon googling I came upon this thread, which is why I started to suspect the Vostro might be a potential culprit. Has anyone any ideas or similar prior experience with this?

 

Most likely a video card issue, have you been using the LaptopVideo2Go drivers? Try one such as the 169.09 and see if it still occurs.