Can't switch to external monitor anymore

[JUser]

I'm running Windows XP on an older Siemens-Fujitsu Esprimo Mobile 6535 laptop (native res. 1200x800) with a Mobile Intel® GMA 4500M graphics chip.

I need to connect it daily to an Acer 2216W monitor (native res. 1650x1050) via VGA cable (there's no digital-out on the laptop). It never worked instantly, but after a few tries it usually did, for several years.

Lately, the problem got worse and worse. Last week I spent nearly half an hour pressing Fn-F10 again and again before I had a picture on the monitor. Every time I try to switch displays, the monitor flickers once before going black again.

The funny thing is, when I set the secondary display to the Acer's 1650x1050 resolution and switch back and forth, the monitor flickers, goes black and the laptop switches to a 1650 resolution.

In the Windows system display I find five nondespript monitors. A free tool (EDID Viewer) to read monitor settings from the Windows registry shows nine, one of which should be the laptop display.

I've updated the Intel Graphics Media Accelerator Driver yesterday, to no effect. The new version properly identifies the Acer monitor, but that's it.

What's wrong here?

[Allan_J_Intel1]

Thanks for joining the Graphics community.

Have you tried changing VGA cable? It does not appear to be driver issue, since you already have the latest version 14.42.15.64.5420

https://downloadcenter.intel.com/SearchResult.aspx?lang=eng&ProdId=2991 Intel® Download Center

Please filter by operating system and check driver version.

Did you test another monitor? This will help you test the video port as well.

Allan.