Why does my HP 34X monitor have a problem turning on for my MacBook Pro?

[MacLover2011]

I'm running a MacBook Pro 16 inch that I purchased in 2019. The processor is 2.4 GHz, 8-Core Intel Core I9. My memory is 32 GB and the graphics card is an AMD Radeon Pro 5500m 8GB.

I just purchased an HP 34 inch flat screen monitor. I am using a J5Create USB-C to 4K cable to plug in the monitor into my MacBook Pro.
My MacBook Pro Built-in Retina Display is the main display. and the HP X34 monitor is the Extended display. I have the HP at 60 Herz refresh rate....

Why does it blink on and off, and has a problem turning on when I hook it up to my MacBook Pro?

Thanks!!!

 

[Raz0rEdge]

What happens when you try this sequence?

• Unplug monitor from MBP
• Turn it on to see the No Signal message (or similar)
• Plug it into the MBP

Does the monitor get correctly detected and depending on your display settings show the right information and continue showing it?

What happens now if you put the MBP to sleep, wait for the monitor to sense the lack of signal, go into power-safe mode itself and then wake up the MBP only. Does the monitor turn on or does it continue to have issues with the signal detection?

The first test will tell you if the cable you are using is able to pass stable video data when everything is powered on. The second test will tell if it's able to send the the right type of data for the monitor to get into the right mode and allow both the MBP and monitor to detect each other.

I had this problem with an external monitor and my old iMac whereby when the iMac woke from sleep, the monitor might or might not wake up. If I manually work it up, it might or might not display the correct info. However, if I manually turned it on and unplugged/re-plugged in the cable, it would always work. A different cable based on reviews fixed the issue for me.

You might be running into a similar issue and might need to try out a few cables to find the one that works for you.

 

[lclev]

Agree with Ashwin (Raz0rEdge). I had the same issue and when I upgraded to a better 8K cable - even though my monitors are 4K - the issues stopped. I was using 4K cables and they did what you are describing.

Lisa

 

[jsteave]

I'm running a MacBook Pro 16 inch that I purchased in 2019. The processor is 2.4 GHz, 8-Core Intel Core I9. My memory is 32 GB and the graphics card is an AMD Radeon Pro 5500m 8GB.

I just purchased an HP 34 inch flat screen monitor. I am using a J5Create USB-C to 4K cable to plug in the monitor into my MacBook Pro.
My MacBook Pro Built-in Retina Display is the main display. and the HP X34 monitor is the Extended display. I have the HP at 60 Herz refresh rate....

Why does it blink on and off, and has a problem turning on when I hook it up to my MacBook Pro?

Thanks!!! Tritech paint sprayer Los Angeles

I have a new 2016 HP monitor and I will not work on both of my MacBook pros! I have mini display port to HDMI into the monitor, and nothing but a black screen shows. I tries messing with every setting, I searched every forum on this issue, I changed cables and adapters numerous times, I purchased a usb to HDMI adapter and that did not work, nothing works! I have not tried VGA but I do not want to use VGA as the HDMI picture is better. But interestingly enough ofter people with MacBooks pro were able to use the HP monitor fine via HDMI with no hassles at all, like plug and play. I am running sierra on both my macs so everything is up to date, It makes no sense why this does not work with a mac, however it does work when I plug into my windows laptop, I know this is not an apple product but it should still work.

 

[MacLover2011]

Thanks everyone for your replies. It turns out it was a cable issue.

 

[MacLover2011]

Suddenly my monitor started blacking out again!!!
I'm using a j5 Create USB-C to 4k cable.

 

[MacLover2011]

Agree with Ashwin (Raz0rEdge). I had the same issue and when I upgraded to a better 8K cable - even though my monitors are 4K - the issues stopped. I was using 4K cables and they did what you are describing.

Lisa

I just might do what you suggest. Thanks!