[joevt]

Neither. The CSV-1460 uses DisplayLink (software and USB) to do video.

You can connect it to a Type-A port and get the same result.

I am unfamiliar with the DisplayLink software or how it interacts with the GPU. I suppose it’s possible to have a GPU render to a RAM buffer and have DisplayLink output that? GPUs are faster when rendering to their own VRAM. DisplayLink also has to compress the info (12 Gbps for 4K 60Hz 8bpc RGB) down to USB 3.0 speed (5 Gbps).

Maybe you can go to the https://www.displaylink.com website to find answers.

A real display connected to a real GPU should appear in the Device Manager (view by connection) as a display device with the GPU device as the display’s parent.

[joevt]

The hub has three parts: a USB 2.0 hub for USB 2.0 devices, a USB 3.0 hub for USB 3.0 devices, and a Gigabit to Ethernet adapter connected to the USB 3.0 hub (because Gigabit is faster than USB 2.0).

First you need to find the USB 3.0 hub in the Device Manager (view by connection). Then one of the ports of the hub must be for the USB Gigabit Ethernet Adapter.

If the “port reset failed” message is next to the hub or one of its ports, then maybe there’s a problem. In that case, you need to test the hub with a different USB port or computer to see if the problem exists in all situations or just this situation.

 

[joevt]

For the display, you’ll need to connect it directly to the laptop’s Mini DisplayPort port. DisplayPort (or Mini DisplayPort) is preferable to HDMI because it has more bandwidth.

There are some adapters that can convert HDMI 2.0 or 4 lanes of DisplayPort, plus USB 2.0 to USB-C, but I believe the CSV-1564 requires two lanes of DisplayPort and USB 3.x.

There are chipsets that will do the job (4 or 2 lanes of DisplayPort + USB 2.0 or USB 3.x) but no-one has made an adapter for it. The Sunix UPD2018 is close, but the USB source is a PCIe USB controller – your laptop has no external PCIe connectors. It has internal PCIe connectors (Wifi or NVMe) but connecting them to an external PCIe device is clunky. Other PCIe cards that do a similar job as the Sunix are Thunderbolt 3/4 add-in cards such as the GC-ALPINE RIDGE, GC-TITAN RIDGE, and ThunderboltEX 4 (they have a USB controller and a Thunderbolt or USB4 controller).

There’s this thing which does everything we want but it doesn’t exist: https://www.bizlinktech.com/products/detail/1332/VirtualLink™+Interface+Adapter

 

[joevt]

Are we talking about the laptop at https://www.gigabyte.com/Laptop/AORUS-15G–RTX-30-Series ?

I don’t see anywhere in the documentation that the USB-C port supports DisplayPort Alt Mode.  The USB-C port doesn’t have a DP icon. In that case, a USB-C dock’s display ports are not going to work.

I also don’t see anywhere in the documentation that the USB-C port supports Power Delivery input. In that case, you need to use the laptops’s charger.

The older Aorus 15G laptops (with RTX 20 Series) had a Thunderbolt port but I don’t know if it supported any displays from the port.

If you want a USB-C port that works properly, then consider laptops that advertise Thunderbolt 4. Intel’s minimum specs for Thunderbolt 4 won’t allow manufacturers to skimp out on features (such as not supporting two displays or full PCIe bandwidth or power delivery).

[joevt]

Is the CAC-1510-A connected directly to the MacBook Pro? Holding the Option key and clicking “Scaled” should show all the modes including 2560×1600.

The CAC-1510-A cannot do 2560×1600 if it’s connected to a USB-C dock that supports USB 3.x but it should be fine when connected to a Thunderbolt dock. The reason is that it is limited to HBR link rate which requires 4 lanes to do 2560×1600 and USB-C docks that support USB 3.x only support two lanes.

The AGDCDiagnose command in macOS tells you the DisplayPort connection type (link rate and link width). The CAC-1510 should be [DP 1.2 4 x HBR ]

 

[joevt]

In macOS, the AGDCDiagnose command can probably get the Firmware version of the adapter. Mine has FW version 0.0 which I guess is kind of useless if they didn’t bother setting a firmware version in the firmware update also? (but I haven’t seen the FW update so I don’t know if they changed the firmware version)
 #21 

 

[joevt]

If the monitor does not have a USB-C port, then you need one cable for video (DisplayPort or HDMI) and another cable for data (USB 3.x).

If you still want only one cable to your laptop, then you need a USB-C or Thunderbolt dock. Then you can connect the two cables from the display to the dock and one cable from the dock to the laptop.

If your laptop supports Thunderbolt 3/4 or USB4, then a Thunderbolt dock would be the best dock option for max video and a data bandwidth.

A USB-C dock may also work. If the display is 4K 60Hz, then you’ll want a USB-C dock that does not support USB 3.x so that all the bandwidth can be for video. CableMatters has some USB-C docks that can do that (they support USB 2.0 only).

A USB-C dock that supports USB 3.x will be limited to 4K 30Hz unless the dock and laptop and display supports DisplayPort 1.4 (HBR3). If the display doesn’t support HBR3, then an MST hub can convert two lanes of HBR3 to four lanes of HBR2. Some docks have a MST Hub built in to support multiple displays.

The CalDigit SOHO is a simple USB-C dock supporting USB 10 Gbps and DisplayPort 1.4 with DisplayPort 1.4 MST Hub which also support DSC (all DisplayPort 1.4 MST hubs should support DSC – it might require a firmware update though). If the laptop has a Navi or RTX or Intel 11th gen graphics then DSC can be used to effectively double the bandwidth – the MST Hub can decompress DSC input for displays that don’t support DSC.

[joevt]

The manual doesn’t say the USB-C port can do DisplayPort output.

It describes the USB-C connector as being able to do that (plus PCIe – which means USB4 or Thunderbolt) but it doesn’t say this particular laptop does anything more than USB 3.x with the port.

[joevt]

I’m not sure if Nvidia exposes the info anywhere about when it’s using DSC. I don’t have an RTX card to test. Try the Advanced tab in GPU-Z?

[joevt]

No adapter is going to uncontaminate a video signal. The video signal is generated by OS drivers using a GPU so your solution would have to involve removing those if the driver does not have the settings you need to not contaminate the video signal in the first place.

A video signal generated by a DisplayLink adapter may have less contamination but I don’t think that’s what you want. It uses compression to transmit video over USB 3.0 (max 5 Gbps but probably less).

[joevt]

DSC is not a function of the cable. It is compression done by the GPU. With compression, an error causes greater artifacts in the display. Without compression, an error is less noticeable.

Errors increase when you chain cables together, especially if they are passive (don’t contain a retimer or redriver or repeater to boost the signal for the next part of the transmission). I think the KVM is passive. I wonder what kind of switch it uses – or what components exist between the inputs and output of the KVM?

Is the 3090 transmitting HBR3+DSC or HBR2+DSC? I know that the Apple Pro Display XDR will use HBR2+DSC for 6K 60Hz 10bpc (1286 MHz). HBR2 is only 5.4 Gbps. HBR3 is 8.1 Gbps so it will have more errors. A G9 supporting 5120×1440 240Hz uses a pixel clock of 2018.5 MHz which can be done with HBR3 at 8bpc 4:2:0 or HBR3+DSC (at least 8bpc, not sure about 10bpc; 4:2:0 is a simple 2:1 compression method – DSC can do up to 3:1 and is smarter about what information it throws away).

Shorter cables may help. Maybe a DisplayPort 1.4 repeater will help. Maybe you can use an MST Hub as a repeater.

https://store.level1techs.com/products/14-display-port-kvm-dual-4ports
https://www.youtube.com/watch?v=wfJ1Hc96ZHo

[joevt]

The CAC-1510 works with single link DVI and dual link DVI displays. Your MacBook Pro has four USB-C ports so you should be able to use 4 adapters (maximum two adapters per Thunderbolt controller which means two per side).

There are two versions of the CAC-1510:
1) CAC-1510 HDCP ON
2) CAC-1510-A HDCP OFF (for Apple displays that don’t support HDCP)

Does your A1082 support HDCP? Read here: #24 

If it does support HDCP, then it should work with either of the CAC-1510 adapters.

[joevt]

@alfuzzy If you have a Apple 30″ Cinema Display that works with the HDCP-ON adapter, then maybe you have a newer Apple 30″ Cinema Display than I have?

Grab the EDID (maybe use the AGDCDiagnose command on an Intel Mac – I don’t know how to get the EDID from an M1 Mac), then use edid-decode to decode it.
https://git.linuxtv.org/edid-decode.git/about/

I have EDIDs for three DVI Apple Cinema displays (23″ and 30″). The newest one supports HDCP:
– Apple 30″ Cinema Display from 2005 product ID 0x9232 = 37426 has a “Display Information Extension Block” that says “HDCP is not supported”.
– Apple 23″ Cinema HD Display from 2006 product ID 0x9223 = 37411 has a “Display Information Extension Block” that says “HDCP is not supported”.
– Apple 23″ Cinema HD Display from 2008 product ID 0x921c = 37404 has a “Display Information Extension Block” that says “HDCP is supported”.

[joevt]

I made a new thread for discussion of the LT6711GX chip at https://insights.club-3d.com/thread/hdmi-2-1-to-usb-c-displayport-1-4-alt-mode/

[joevt]

You have an LG UltraFine 5K.

If the current adapter (CAC-1332) can work with the LG UltraFine 5K then it probably only works at 4K width because of the LT6711 chip it uses.

If there was a new adapter using the new LT6711GX chip (I have not found any yet) then you could get 5K width from some HDMI 2.0 sources. The LG UltraFine 5K is limited to 600 MHz pixel clock with a single DisplayPort 1.2 connection, so it would have to be 5K39Hz. Two reasons this might not work:
1) The M1 Mac doesn’t have a method to add custom timings.
2) The M1 Mac mini might not support 5K width from its HDMI 2.0 port (because it uses the MegaChips MCDP2920A4 DisplayPort 1.4 to HDMI 2.0 converter which is also used by the Apple TV and Mac mini 2018 and Radeon Pro 580X MPX module).

If the CAC-1332 is connected correctly (the CAC-1332 is connected to a USB-A port with sufficient power and a USB-C cable that can transmit 10 Gbps to a USB 3.1 gen 2 drive is connected between the CAC-1332 and the display’s Thunderbolt input) and the M1 Mac mini still doesn’t detect a display, then there’s nothing else for you to do.

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