It's not a missing monitor driver (monitor don't have drivers, although they come with .inf-files that describe their capabilities), but a missing driver for the graphic card.
As Dell usually sells its machine is different configurations (that can have different videocards depending on the customers wishes) we can't tell what card it contains and what driver you need.
Your best chance is to download Belarc Advisor (free) and see what it finds out about the video card. Armed with that knowledge visit the download section of dell.com (or nvidia.com or ati.com, depending on what it finds).
Monitors are highly interchangeable. So you don't need a Dell monitor.
hi, I've just purchased a 2nd hand dell optiplex GX260 it's hard drive has been wiped clean so i've had to install the OS (windows XP Pro is now on)but after doing this i've found that the screen resolution will not change i think that i may not have the right driver installed for the monitor i'm using ? the monitor i'm using is not a dell does that matter ? do i need a dell monitor ? the screen resolution is 640 by 480 pixels at the low side but if you try to move it to higher it will not move ?? do i need new drivers ? if so can anybody give me a link to where i can get it from ? i'm not very good at finding these things ?for any help i would be grateful, Thanks Steve.