On 23/09/2019 13:10, Nicolas Kovacs wrote:

Hi,

I have a CentOS 7 desktop client installed on an old Dell Optiplex computer with an Intel video card integrated into the motherboard. The card has a single VGA connector, and the 19" monitor is connected to it.

I wonder how I could connect a video projector to this computer while keeping the monitor, in a mirroring configuration, e. g. output is the same on the video projector and the monitor.

Do I have to replace my onboard video card by something like an NVidia GT710 graphic card with two video connectors ? Or is there a different solution for this?

If you are not concerned about not being able to dual-screen (i.e. have different things displaying on the monitor to what is on the projector, then the easiest way is to just get a VGA splitter.

https://www.amazon.co.uk/AmazonBasics-VGA-Monitor-Splitter-Black/dp/B06XJNMD... https://www.amazon.co.uk/AmazonBasics-VGA-Monitor-Splitter-Black/dp/B06XJNMDBL/ref=asc_df_B06XJNMDBL/?tag=googshopuk-21&linkCode=df0&hvadid=309981988222&hvpos=1o2&hvnetw=g&hvrand=8312392659667639436&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006978&hvtargid=pla-366774003587&psc=1&th=1&psc=1

If you do want to dual-screen, you should replace the embedded intel with a dual-screen compatible card with the appropriate output connectors. This is sometimes useful for presentations, as you can put the presentation on the projector and keep presentation notes on the screen.

I think most Optiplex systems support this, things to check:

* Look in the BIOS for the system, there should be a setting about which GPU to use, without an additional card inserted in the system the only working option here would be something like "Integrated Graphics", but when you fit a new GPU to a slot the new GPU will become an option or it may allow you to choose a PCIe (or AGP on older systems) - this could give you a clue about what type of GPU you need to get.

* Check the form factor (i.e. size of slot & space available) - some Optiplexes are small, so you might need a low form-factor card.

* Check slot type, most cards today are PCIe, older models might only have a AGP card - which will be harder to find new.

* Check bandwidth of PCIe slot - most whizzy cards need a x16, Optiplex might only have a x8 or x4.