Inspiron 5515, maximum screen resolution for external monitors

You certainly can get 4k from USB type C to Displayport 1.4 connection 

You can get FHD from HDMI 1.4 connection.  Or maybe 4k at 30hz, using high quality cable.

Thanks for the answer!

I was able to get 4k resolution @ 60hz from the USB type C 3.2 port to HDMI input on the monitor. 

Now to see if I can get a refresh rate of 100hz on a 3440 x 1440 UWQHD monitor with the same connection. Or would Displayport be better than HDMI?

The maximum screen resolution for external monitors on either the USB C 3.2 port or HDMI port for the Inspiron 5515 Ryzen 7 with AMD Radeon internal graphics is 1080p. This is because the motherboard of the laptop only supports a maximum resolution of 1920x1080 or 1920x1200 on the HDMI connector. Therefore, even if you connect a 4K monitor to the laptop, you will only be able to use it at 1080p.

Displayport will give you higher bandwidth over HDMI to achieve higher refresh rate.

@anyabaker 

I have found through testing that this is not the case for this laptop. I was able to achieve 4k @ 60hz through USB type C 3.2 to HDMI with a quality cable. 

Updating post to say USB type C 3.2 port on the Inspiron 5515 with AMD Integrated Graphics can achieve a resolution of 3440 x 1440 @ 100Hz via DisplayPort connection on the monitor. 

I don't have any higher resolution monitors or I would continue testing.

This is impressive for a laptop!

Good work, glad to see it worked out well for you.