Glenwing

HBR3 maximum data rate is 25.92 Gbit/s, which is a physical bit rate of 32.4 Gbit/s. Requirement for 2560×1440 at 240 Hz 10 bpc is 30.77 Gbit/s data rate, which becomes 38.46 Gbit/s bit rate in HBR3 transmission. So it would be outside the limit. But you are comparing the data rate requirement of one against the bit rate limit of the other, which is incorrect If the monitor only supports HBR3, then either it uses DSC, or does not allow 240 Hz and 10 bpc simultaneously. In either case only HBR3 rated cable is needed, anyway.

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There are no specific refresh rate limitations on any interface. HDMI is limited to 144 Hz at 1440p due to its maximum bit rate, if 8 bpc RGB color is used. If the monitor is 1080p, or any of those other things change, the maximum refresh frequency will change.

DVD Video is 720×480 at 29.970 fps for NTSC format or 720×576 at 25 fps for PAL format. TVs use 59.94 Hz, and DVD players transmit each frame twice. For sources originating from 23.976 fps film, 3:2 pulldown is used to convert it to 29.970 fps for DVD Video. So this is already built into the images on the DVD. Almost any monitor will already have a CTA-861 profile that runs at 59.94 Hz. Using CVT will not allow you get such an exact rate due to the requirement that the pixel rate be an even multiple of 250 kpx/s. It may be more worth it to just make a custom resolution at 1920×960 (that is, 480×2 lines) then display it with aspect ratio scaling. You'll get thin black bars on top and bottom but then the 480-line image will be scaled 2:1 precisely (if you set scaling to maintain aspect ratio). And it can be based on the standard CTA-861 modeline. $ xrandr --newmode "1920x960x60" 148.3515 1920 2008 2052 2200 960 964 969 1125 +hsync +vsync

Sounds like AMD is not implementing something correctly in their driver. Download the Custom Resolution Utility here: https://www.monitortests.com/forum/Thread-Custom-Resolution-Utility-CRU Select the 1440p monitor at the top, then select the CTA-861 extension block and click "Edit": Select the TV Resolutions data block: Delete all the 4K entries: Click OK on everything, then restart the graphics driver using Restart64.exe Then the 4K profile should be gone, and it should use 1440p.

Some 1440p monitors accept 4K resolution input signals on HDMI. This is for compatibility with older consoles (PS4, Xbox One) which only let you choose between 1080p and 4K. So on 1440p monitors they would be forced to a 1080p limit. To avoid this, monitors accept a 4K signal and then downscale internally to 1440p. If you have GPU Scaling enabled in the AMD Adrenaline settings, the graphics card will always output a signal at the monitor's maximum resolution regardless of what resolution you set the desktop to. If you choose a lower resolution, it will upscale it to the monitor's maximum resolution before transmitting. Unfortunately this combines in a bad way with the 1440p monitors that accept a 4K signal, as it just takes your 1440p original image and upscales it to 4K, transmits it, and then it's downscaled back to 1440p on the other side, resulting in quality loss from the double conversions, and also limiting you to 60 Hz because of the increased resolution during transmission. To avoid this, turn off GPU Scaling in the graphics card control panel, or don't use HDMI.

It's done in dedicated hardware which is part of the DisplayPort transmitter. It isn't done by NVENC.

G-Sync module monitors are hard-limited to 60 Hz on the HDMI input.

The L1Techs model may work, as it supports Display Stream Compression which is what's needed for 5K 240 Hz to work. Not tested personally though. https://www.store.level1techs.com/products/p/14-kvm-switch-single-monitor-2computer-64pfg-7l6da

I should note on the product page of the KVM it says:

That's what he's doing right now. But he'd like the button on his KVM to switch K, V, and M. Not just K and M and then switch the video separately.

That could probably work. Since it uses an external power supply, it shouldn't rely on the 3.3 V from the port.

A DisplayPort to HDMI adapter needs to be connected directly to the PC. It relies on 3.3 V power from the DisplayPort port. Normal DP to DP cables do not carry this power through the cable, it is only available from the port. So adapters will not work through an extension like that.

It supports whatever it supports, the video capabilities are not related to the USB generation. It's a direct output from the GPU so it will just be based on the DisplayPort capabilities of the GPU. https://linustechtips.com/topic/729232-guide-to-display-cables-adapters-v2/?output=USBC Based on what I can find about the AMD 7730U, it should support the formats you mentioned. https://www.amd.com/en/products/apu/amd-ryzen-7-7730u 4K 60 Hz and 1440p 120 Hz only require HBR2 speed which has been doable with DisplayPort for around 10+ years.

The one you linked seems to be ok.

No, most cheap DP to HDMI adapters/cables are limited to 1080p 60 Hz. You need a Type 2 adapter or an active adapter for higher.

NVIDIA cards have a maximum of 4 monitors. However, 1440p at 360 Hz requires DSC and therefore counts as 2 monitors. So you can have maximum of 3. https://linustechtips.com/topic/1555698-3x-4k-monitors-with-more-then-120hz-each-possible/#comment-16305484

Adapters don't have specific support for "MST"; that doesn't exist. But adapter support on MST outputs will depend on the device. Some work with both passive and active adapters, some only work with active adapters, and some don't work with any adapters. If you've tried passive adapters already then you should try an active adapter.

This is VGA ghosting, it comes from a poor quality analog signal. A better cable may help.

It is because a DisplayPort HBR2 transmission is limited such that 170 Hz and 10 bpc are not possible at the same time at 1440p. It is a straightforward bandwidth limitation and is not related to how 10 bpc color depth is implemented (FRC or not). Since the monitor advertises "DP 1.4" hopefully this means it supports HBR3 speed, so this would not apply. That is what the discussion above was about. Panels are addressed in a matrix format where only 1 row of pixels is actually connected to the controller at any given time. The controller scans through every row in order over the course of 1 refresh cycle. It is not possible to go back and change the color of a pixel twice during one refresh cycle as this would simply be the same has having a twice as high refresh rate, and this capability would not be wasted on simply implementing FRC. FRC operates by changing the color on alternating refresh cycles, not within a single cycle. My suspicion is that the monitor only supports HBR2 speed, and when ViewSonic says it has "DP 1.4" they just mean it supports HDR or something else. I should note the user manual states only "DP 1.2".

That makes no sense, the use of FRC is not related to refresh rate, nor does the system know whether the monitor uses FRC or not; it just sees a 10 bpc display.

Some monitors have menu options that control the DisplayPort feature level, try checking for this.

Yes, you can plug each one into a separate DisplayPort output on the graphics card.

Mac OS does not support MST. For the PC, you may have to set some menu options in the monitor. According to the manual section 1.3.4 there may also be some limitations when you have the USB-C cable connected at the same time.

What graphics card is on the PC?