UGA-4KDP not working at 3820-2160 with 50" Seiki monitor, does work at 1920x1080

Hello! I just purchased your UGA-4KDP unit from Amazon.

Not working at 3820/2160 - 30Hz. Does work at 1920x1080.

Any ideas?

How do I change the internal setups in Windows 8.1 on my Lenovo Yoga 2 Pro laptop to get it to work?

I am connecting to a Seiki 50" 4K monitor that works fine on my desktop (Windows 8.1 with PNY Quadro 410 card). I have the monitor technical details in a file if you need them.

thanks
Jim

We’ve been working with Jim via our private email ticketing system on this issue, but for the benefit of others doing research/troubleshooting, we’re posting the findings here as well.

The UGA-4KDP requires an active adapter to convert to HDMI at resolutions above 1080P. Using a passive adapter will generally result in higher resolutions not working correctly. (On our test 39" Seiki when I use a passive adapter the TV will either not offer 3840x2160, or if it does offer it it will just say “Not Support” if this resolution is selected.)

Thanks!
Gary