Acer monitor issues

[danny842003]

Hi I recently purchased two acer monitors (G236HL) to run with my MacBook pro retina 2015. As a stop gap I borrowed a HDMI cable to run one screen from the HDMI port and another mini display port to HDMI adaptor and cable to run the other. This works fine but I have over uses for those cables.
Since them I have purchased some mini display port to HDMI cables from eBay which the monitors wouldn't register but a TV would. I was refunded for those.
Then two mini display port to dvi-d cables which wouldn't register either.
This morning i went to a local electronics store and purchased a ore expensive mini display to HDMI cable and the same thing nothing from the monitors but works fine on a TV. Has anyone got any idea what the issue could be?

I have tried the detect display function with no change.

 

[KevinJS]

I'm at a total loss. The fact that you have had it working with certain cables, but can't get it working with others points to an issue with the cables rather than the computer or monitors.

I'd buy a couple of the Belkin cables that Apple sells for this application and see whether they do the trick. At least if you start with the equipment the manufacturer recommends, you have a starting point in trying to figure out what is wrong. HDMI 1.4, which the rMBP outputs, should handle 1920x1080 with no problems.

 

[danny842003]

Ok so I did buy a Belkin cable and it seems that one of the thunderbolt ports will output to a TV but not to a monitor. Looks like a trip to a genius bar unfortunately.

 

[danny842003]

Just to add I was playing around and now I'm in the situation where I can display from the thunderbolt port I previously couldn't but now the one which was working isn't any longer.

 

[KevinJS]

Seems that you don't have a cable issue. If they work once, they should be able to work every time. HDMI is a digital system. It either works or it doesn't. There's no middle ground.

I suspect you have a timing issue. HDMI can be pretty finicky if it doesn't get what it wants, when it wants it. I suggest hooking everything up with the computer and the monitors turned off, then turn the monitors on, followed by the computer. If that doesn't work, turn the computer on first. It might be worth going to Display Preferences, and selecting "Default For Display" to ensure that you are not attempting to send a video signal of more than 1920x1080. You won't send any more through your computer's HDMI port, but you may through the Mini DisplayPort. If so, it will confuse the HDMI end of the cable.