I remember reading somewhere that 60HZ is only supported through DP not HDMI. I don't know how others managed that though.
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The new Dell U2718Q 4K monitor
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I remember reading somewhere that 60HZ is only supported through DP not HDMI. I don't know how others managed that though.
So I just drove down to Best Buy and bought 2 absurdly priced USB - C to 4k HDMI cables from J5 create ($40 a piece) and it's working now and both show 4k/60hz.
I still have to figure out why the mDP isn't broadcasting at 60hz but I suspect that has more to do with a cheap amazon cable I purchased that says 4k.. when I go back to the order page there is nothing mentioning anything regarding 60hz so perhaps that is the reasoning for that.
Still unsure why the mDP to DP wouldn't work at 60hz but this has definitely been a learning experience.
I still have to figure out why the mDP isn't broadcasting at 60hz but I suspect that has more to do with a cheap amazon cable I purchased that says 4k.. when I go back to the order page there is nothing mentioning anything regarding 60hz so perhaps that is the reasoning for that.
Still unsure why the mDP to DP wouldn't work at 60hz but this has definitely been a learning experience.
I use this mDP to USBC cable from Cable Matters for $18. It works great at 60Hz. Had to replace it once because of some glitch but the service was great. They also have DP to USBC, works great on my P2715Q as well.
https://www.amazon.com/gp/product/B0777S15V2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0777S15V2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
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I'm glad you got 60Hz. Some time ago when I bought Dell U2718Q and went to purchase my MBP 2017, I read much about those cables and getting 4K/60Hz and found out a couple of things:
— They are not cheap: HDMI is a bit cheaper, DP is more expensive. The issue with DP comparing to HDMI was about incorrect colors which have been fixed by Dell via a firmware then
— Everything about USB Type-C has only three letters common to the previous USB experience, nothing more, especially in terms of price
Less expensive dongles give you only 4K/30Hz.
You might buy Plugable's USB-C to HDMI cable. It works well because Dell U2718Q is capable of HDMI 2.0 as well a cable itself. I preferred it to USB-C to DP because HDMI option is more universal for home (I also have 4K Samsung Smart TV where the cable fits well). Though j5create cable-adapter I use in my office and yes, it was crazy expensive.
But how? 8K? How did you get it?
— They are not cheap: HDMI is a bit cheaper, DP is more expensive. The issue with DP comparing to HDMI was about incorrect colors which have been fixed by Dell via a firmware then
— Everything about USB Type-C has only three letters common to the previous USB experience, nothing more, especially in terms of price
Less expensive dongles give you only 4K/30Hz.
You might buy Plugable's USB-C to HDMI cable. It works well because Dell U2718Q is capable of HDMI 2.0 as well a cable itself. I preferred it to USB-C to DP because HDMI option is more universal for home (I also have 4K Samsung Smart TV where the cable fits well). Though j5create cable-adapter I use in my office and yes, it was crazy expensive.
But how? 8K? How did you get it?
USB-C docks are only capable of 4K 30Hz because two of the four lines are used for USB 3.x. You need a Thunderbolt dock. I don't think the Henge dock is Thunderbolt even though it says 40 Gbps data throughput. Check the Thunderbolt section of System Information.app.
There are two types of USB-C or DisplayPort to HDMI adapters.
Passive - these are usually limited to HDMI 1.4 (4K 30Hz)
Active - these can do HDMI 2.0 (4K 60Hz).
Passive relies on the DisplayPort dual-mode port to output an HDMI signal. The adapter only needs to change the voltage levels. DisplayPort 1.2 dual-mode is limited to 4K 30Hz.
Active takes a DisplayPort signal and converts it to HDMI. Some may still be limited to 4K 30Hz?
Dual-mode is not part of USB-C so I don't think there are any USB-C passive adapters. Actually, there's an HDMI alt mode for USB-C but I don't think there's any USB-C ports that support it?
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System Information.app gives no description of the actual signal that is output from the graphics card (output resolution, timing, color depth).
8K is a scaled resolution. The graphics card scales it to the output resolution. You can create any scaled resolution using SwitchResX, regardless of the actual resolution of your display. The scaled resolution can be larger or smaller than the actual resolution.
Use the SwitchResX application to view the timing information of the current resolution (double click the current resolution in the Current Resolutions list). It will tell you the pixel clock, horizontal and vertical refresh rates, blanking pixels, etc.