Having the same problem come back is best handled in the same thread so that the people that already helped you will know that you've updated the thread & so that them (and others) will better know what is going on. Have you tried installing a new graphics card? I saw something about an nVidia graphics card; their drivers might have settings to force windows to display the monitor at the proper dimensions. Play around with that. You should try installing the drivers of that monitor so that Vista will know exactly what monitor you are using a what dimensions that it can use. You should have gotten a setup disk with the monitor if not download them from the HP website & be careful that you get the drivers correctly. Also if this monitor is new then you should be able to contact HP for live help.

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1) State your OS(s), any software involved in your problem, & any major updates (i.e. service pack, version, edition, service release, roll up, beta release, distribution [Linux], etc.) to your OS/software as applicable to your problem.
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If you don't know your system information please consider running our hardware scan and post or PM me your link.