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Topic: Trouble connecting Optoma UHD35 to Macbook Pro
Joined: Jan 8, 2022
Posts: 8
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I've run into issues setting up my Optoma UHD35. My video source is a mid 2015 15" Macbook Pro. My AVR is a Pioneer VSX-921.

I ran an HDMI 2.0 cable from my MBP's HDMI port to the AVR.
I connected an active mini displayport adaptor to my Thunderbolt 2 port, which allows me to run a second HDMI 2.0 cable to the Optoma.

I set the Optoma as the main display and the MBP and AVR as extended displays, each at their so-called default resolution.

I set the Optoma to its default resolution and to 60 Hz. One discrepancy is that when I press the HDMI 1 source button on the Optoma's control, it reports 2160p at 30 Hz, not 60 Hz. But when I visit to measure the refresh rate, testufo reports 60 Hz? if that's true, why is the Optoma reporting 30 Hz?

The other issue is that sometimes when I connect everything the same exact way, the Optoma will report 2160p at 60 Hz but now the screen is either flickering colorful horizontal lines, a complete green screen, or a black screen with green horizontal bar across the top.

I don't understand why it's inconsistent and kind of hit or miss. And I don't understand why when I AM able to see the Optoma's screen it is reporting 30 Hz when I press the source button but says it's at 60 Hz. What's happening here, is it a faulty active mini displayport adapter or something else entirely?

Some help here would be very much appreciated. Thank you
Joined: Mar 28, 2005
Posts: 13,307
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Unfortunately, computer issues are almost always an issue with the computer in use. It is possibly the adapter as you should just be using a Thunderbolt to HDMI adapter, you shouldn't be using multiple adapters if avoidable. USB-C to HDMI should be a direct conversion, still I have seen adapters which do not work.

A potentially very big issue is whether or not your laptop actually supports 4K/60 resolution. This is not always a given. A very big thing in the industry is to advertise "4K SUPPORT!", but really they mean 4K/30 support, not 4K/60 support. So, you would need to check your laptop specifications.

Likewise, across the board, you want to ensure that 4K/60 support is not only part of the specifications, but that it is enabled on all products throughout the lineup.

Finally, plug your laptop DIRECTLY into the projector. Bypass all other equipment in the path, and see if you get a proper video signal at 4K/60. This can indicate that your cabling in use isn't properly supporting the 4K/60 signal that is in place. If you are 6' from a projector using a good 4K/60 rated cable and it works, then move 30' away and it doesn't work, it indicates your 30' cable isn't properly supporting the resolution. Then try it through the receiver.

But, I would start with a short HDMI cable between the laptop and the projector and see what results you get.
AV Integrated - Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.
Joined: Jan 8, 2022
Posts: 8
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Thanks for your response.

My laptop can function and output 4K 60Hz. It cannot do so via its HDMI port, though, since it has a max of 4K 30 Hz. There is no USB-c port. This leaves me with the thunderbolt 2 port, which reportedly can handle 4K 60 Hz. An active mini displayport adapter is required to plug into the thunderbolt 2 port and then an HDMI 2.0 cable is attached to the adapter and runs directly to the projector.

That's as direct as I can go, i.e., through the active mini displayport adapter.

When I set it up this way, the Optoma reports 2160p 30 Hz (when pressing the source button on the remonte). However, if I visit, it reports that the projector is at 60 Hz. Someone in another forum suggested that this might just be a bug with the Optoma.

The other issue is that sometimes when I connect the Optoma it reports 2160p 60 Hz (when pressing the source button on the remonte) but the screen it's a green screen or a green bar across the top of a black screen.

Likewise in another forum they suggested that the green screen could be the result of a poor connection with the adapter in the port or the cable. However, what's strange to me is that at times that I see this greenscreen the Optoma reports 60 Hz. So, there are still some oddities and discrepancies here. I ordered a new adapter and hopefully that will solve the connection issues.