DP-HDMI 2.0 4k60 signal cuts out every 30-60 seconds

My Plugable adapter cuts out (black screen) every 30-60 seconds for a few seconds, which is the same behaviour I had with another adapter before buying the more expensive (hence my assumption of better QC) plugable one. It’s connected to a very sturdy 25 foot HDMI cable. When I plug the 25 foot HDMI directly to my RX570 video card, I get perfect stable picture at 4k60 with no cut outs so the cable is not the issue, but unfortunately my RX570 has 1 HDMI 2.0 output vs. 3 DP outputs so I have to use an adapter because I need multiple outputs.

This is either a bug in the chip in the adapter or simply not enough power through the DP port to produce a clean HDMI signal or overheating. I’m running W10.

Hi,

Thanks for reaching out to us, I am sorry this is not working as expected and I am happy to help!

Most likely the issue is not enough power to drive the 25 foot cable, the adapter uses power to convert the signal from DisplayPort to HDMI and has reduced cable length than a native HDMI output. Would it be possible to test the computer, adapter, and the display with a shorter cable to see if this works as expected?

We normally recommend using these adapters with 6ft-9ft Certified Premium HDMI cables whenever possible ( https://www.hdmi.org/spec/premiumcable ). HDMI Certification helps to guarantee the cable meets or exceeds the requirements of the situation.

Thank you,

Pat
Plugable Technology

I have tested with a 6 ft cable with the same results. I ordered a 1.5ft cable and test with that as a last resort. If that does not work, I will confirm that there are no dp->hdmi designs that can handle a 4k60 signal and will just get a video card with multiple HDMI 2.0 outputs instead of the useless DP

Hi,

Thanks for testing with another cable, please let me know the manufacturer name and model number of the 4K display and the hardware manufacturer and specific model number of the graphics card and I will check for any potential incompatibilities.

We have tested our DisplayPort to HDMI graphics adapters with a number of 4K 60 displays, both computer monitors and television without experiencing flashing or blackouts like you are seeing, and with two different adapters showing the same behavior it may be that one of the other devices is causing this behavior.

Thank you for the additional details, I will post back here if I see anything that may cause this behavior.

Pat
Plugable Technologies

I got it working and stable using a 1.5 ft 4k60 rated HDMI cable which I plug into a HDMI signal booster with the 25 ft cable on the other end. It’s a bit clunky but it works and the only way to send a DP-to-HDMI signal at 4k60 4:4:4 from my PC that is in the basement to my office in the first floor, hence the 25FT cable I have.
So it’s all about the cable length and having enough power to send the signal.

Hi,

I am glad it is working! Requiring a 1.5ft cable to achieve the supported resolution may indicate the graphics card’s DisplayPort has a significantly lower power output than I would expect to see on a desktop graphics card. It is also possible the 6ft cable is not rated for or capable of supporting 4K at 60Hz.

If you would like we can keep working to narrow down this, or we can go ahead and mark the thread closed.

Please let me know if you have any additional questions, or how you would like to proceed and we can go from there.

Thank you,

Pat
Plugable Technology
support@plugable.com