@lizcorrell
Hello;
Allow me to welcome you to the HP forums!
If by "splitter" you mean a Y-cable that splits the existing video cable into two cables -- that will not work. All that will do is put the same display on both of the screens, essentially mirroring the original screen.
You need each video cable running from a separate jack on the PC.
If your PC does not have a VGA or HDMI output jack to connect a second cable, then you can spend $40 USD or so to purchase a USB-to-VGA adapter. This allows you to connect a monitor to a video cable, that cable to the adapter, and the adapter to a USB port on your PC.
I use one of these on my desktop to run a third monitor and it works great.
Good Luck
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