As per title
No idea since you didn't give a maker or model number hard to say. You best bet is to ask the support department of the company that made your GPU.
This is what I got, not sure if it helps.
radeon R7 240. three monitors
Thanks but I would have to know whose and what model card it is to go to their website and try to find specs. For instance is your card made by Saphire, MSI, Power Color, etc..... Then what model. On whoever site that made your card will be specs. If it does not answer your question there should be support contact there too and you can ask them.
Do you know how many ports are on the back of your card? You may have several different types could be VGA, HDMI, DVI, Display Port. Some might only have a HDMI and several Display Ports. If it has at least 3 ports it should support at least 3 monitors is my guess. It may be a matter of making sure your monitors support the ports your have or you can get adapters to convert a display port to other types.
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