[joevt]

The CSV-7300 DisplayPort 1.4 MST Hub supports DSC so it should be able to do at least one 4K 144Hz display.

Although DSC can double or triple the bandwidth of DisplayPort 1.4, I don’t know if that’s enough for multiple 4K 144Hz displays.

The MST Hub can do triple 4K 60Hz 8bpc RGB with DSC. That is less than double the bandwidth of DisplayPort 1.4, so I guess DSC is less efficient with MST? Or there are limits to the amount of compression/decompression the MST Hub can do?

 

[joevt]

CAC-1085 works with HDMI 2.0b displays. 4K 120Hz is possible with HDMI 2.0b using 8bpc 4:2:0 chroma sub sampling, but that’s not good enough for HDR. I’m not sure if the CAC-1085 supports 8bpc 4:2:0 chroma sub sampling.

[joevt]

The CAC-1331 only outputs four lanes of DisplayPort 1.2.

The ASUS ROG PG27A only supports DisplayPort 1.2 and HDMI 1.4.

Did you try setting a lower resolution or refresh rate on the PS5 such as 1080p 60Hz or 4K 30Hz?

Have you tested the adapter and display with something else, such as a PC?

[joevt]

4K60Hz uses all 4 super speed lines of USB-C for DisplayPort 1.2 alt mode but USB-C also has separate high speed lines (D- and D+) for USB 2.0 that are always available for USB-C alt modes.

The CAC-1332 would be perfect if it included USB data (at least it would be much better – perfection is a moving target as new specs are introduced like HDMI 2.1). Some displays like the LG UltraFine 4K (which only have a USB-C input) use USB for audio instead of the audio from DisplayPort.

The female USB-C port is especially useful for USB-C devices/hubs/docks that have a non-detachable male USB-C connector. Of course, it would only work with those USB-C devices that don’t require USB 3.x and can accept four lanes of DisplayPort (many USB-C docks won’t work with four lanes of DisplayPort) unless the adapter can switch modes between two lanes of DisplayPort + USB 3.x and four lanes of DisplayPort + USB 2.0 like most USB-C host ports (like any Thunderbolt 3 port, or the USB-C port of some PCs and the MacBook and the Sunix UPD2018, and HP Thunderbolt Dock G2, etc.).

[joevt]

But the CAC-1085 also supports DSC which should effectively double or triple the bandwidth of DisplayPort 1.4.

8K 60Hz is double the pixels of 4K 120Hz per second, so unless the CAC-1085 supports 4K 240Hz, then maybe it should say 8K 30Hz instead of 8K 60Hz? Actually, using CVT-RB timing, 8K 60Hz is 2090 MHz and 4K 240 MHz is 2332 MHz so maybe 4K 217Hz would work (2083 MHz) if 8K 60Hz does. Well, maybe it doesn’t matter since we are talking about HDMI – most HDMI timings use multiples of 297 MHz instead of CVT-RB:

4K30 297 MHz
4K60 594 MHz
4K120, 8K30 1188 MHz
4K240, 8K60 2376 MHz
etc.

The RTX and Navi GPUs support DSC (but the CAC-1085 product page doesn’t mention the AMD GPUs, why is that? – maybe it needs to be updated – they can’t update the page every time someone makes a new GPU.

If DSC is not working, 4K 120Hz can be done with DisplayPort 1.4 using 4:2:2.
If HDMI 2.1 is not working, 4K 120 Hz can be done with HDMI 2.0 using 4:2:0.
Same is true for 8K 30Hz. Did you try 8K 30Hz?

NV HDMI is HDMI 2.1. I guess you must have a working HDMI 2.1 cable to get 8K 60Hz.

For NV [DP] DisplayPort 1.4 (HBR3) and DSC need to be working. You’ve updated the Nvidia drivers? You already said you had the latest but doesn’t hurt to double check.

It could be that the cable works with the NV but not the CAC-1085? Not likely but possible.

 

[joevt]

For the CAC 1301:

If 8bpc can do 210 MHz, then I would expect 10bpc to do 210*8/10 = 168 MHz but maybe there’s some overhead I don’t know about.

Those are the max pixel clocks – it should be able to support lower pixel clocks.

1920×1200 60Hz requires 154 MHz (using CVT-RB timing) or 193 MHz (using CVT or GTF timing which is probably what should be used for VGA displays or at least CRTs).

1080p 60Hz is 138 MHz (using CVT-RB) or 148.5 MHz (HDMI) or 173 MHz (using CVT or GTF).

The product page says “DisplayPort 1.1a  compliant receiver offering 5.4Gbps bandwidth over 2 lanes”. Why does it mention DisplayPort for a HDMI adapter? Maybe the DisplayPort part was not meant for this product since it’s not mentioned in the PDF specification sheet? The PDF specification sheet also does not mention the 10 bpc capability. Is the product page accurate? Maybe it should mention what chip it uses so we can look up more detailed/better written specs.

Two lanes of DisplayPort 1.1a can do up to 216 MHz at 8bpc and 173 MHz at 10bpc but there needs to be some room for overhead. 

HDMI 1.4 can do up to 340 MHz 8bpc or 272MHz 10bpc.

 

For the CAC-1302:

This adds analog audio input. It also adds HDCP support even though VGA displays don’t support HDCP?

“165MHZ/1.65Gbps per channel (4.95Gbps for all channels)” This means it’s using max speed of HDMI 1.0 or DVI. HDMI transmits 10 bits for each byte of data, so the amount of data is 3.96 Gbps total.

3.96 Gbps can do 165 MHz 8bpc or 132 MHz 10bpc.

 

VGA adapters in general:

I don’t see any reason to consider 10bpc for analog output. I’m not sure any DACs support 10bpc so you can probably ignore all the 10bpc numbers.

Even if a VGA adapter says 1080p or 1920×1200 is the max, that doesn’t mean that it cannot do more. For example the Plugable USB 3.1 Type-C to VGA Adapter says it supports up to 1920×1200 60Hz but I can get it to do 330 MHz (the adapter supports two lanes of DisplayPort 1.2 which can do up to 360 MHz 8bpc). I haven’t checked with an oscilloscope if the rise and fall time of the VGA output signal between a black and white pixel is less than the period of a single pixel but that’s not as important as the resolution and frame rate in most cases.

[joevt]

The CAC-1080 product page has no info about drivers. What problem were you expecting a driver to fix?

[joevt]

Cable Matters has a new USB-C to HDMI 2.1 Adapter. Product ID 201388.

It’s basically a USB-C version of the CAC-1085 so it probably uses the same Realtek chip. It’s more convenient because it gets power from USB-C (like Club 3D’s USB-C to Dual Link DVI adapters) so it doesn’t need a separate USB power connection like the CAC-1085 does.

Since they probably use the same chip, it might be helpful even if you have a Club 3D product to read information about the Cable Matters product.

https://www.cablematters.com/pc-1368-122-usb-c-to-8k-hdmi-adapter.aspx

https://kb.cablematters.com/index.php?View=entry&EntryID=136

https://www.anandtech.com/show/14535/realtek-demonstrates-rtd2173-displayport-14-to-hdmi-21-converter

 

[joevt]

I suggest you read wikipedia.org about USB-C and DisplayPort.

The signal at the USB-C connector of the CAC-1332 is DisplayPort. It is using the DisplayPort Alt Mode of USB-C. DisplayPort Alt Mode can include USB 2.0. USB 2.0 is used by USB-C displays like the LG UltraFine 4K to do audio, USB ports, and brightness control (all through USB devices). The LG UltraFine 4K requires four 4 of DisplayPort 1.2 to achieve 4K60. Some displays can do audio from the DisplayPort signal. And they can do brightness control using DDC/CI from the DisplayPort signal. I think the LG UltraFine 4K supports audio only from USB but can use DDC/CI to do brightness control (with third party app).

For USB-C DisplayPort Alt Mode, the number of lanes used for DisplayPort can be reduced from 4 lanes to 2 lanes so that the other 2 lanes can be used for sending and receiving USB 3.x. USB 2.0 uses different lines than DisplayPort and USB 3.x.

USB-C DisplayPort Alt Mode is used by USB-C docks and displays. Some docks allow 2 lanes of DisplayPort with USB 3.x, while some use 4 lanes of DisplayPort with USB 2.0. Some displays have an option or automatically switch between USB 2.0 or USB 3.x for the USB-C input (for example, if the display is using a different input, then it can use USB 3.x from USB-C).

The Apple USB-C Digital AV Multiport Adapter uses two lanes of DisplayPort 1.4 (and DSC). This allows the USB port to do USB 3.x.

[joevt]

I have tried the CAC-1331 with my Acer XV273K display and Radeon RX 580 (using CAC-2068 cable).

The CAC-1331 can do 4096×2304 but some timings cause a problem. For example, the native timing of the 21.5″ LG UltraFine 4K display does not work through the CAC-1331 even though the XV273K can accept the timing from HDMI 2.0 or DisplayPort.
[code]
[email protected] 142.198kHz 593.82MHz h(8 32 40 +) v(1 8 57 -) 16:9
[/code]
Some CVT-RB timings for 4096×2304 do work (50Hz, 51Hz, 53Hz, 57Hz, 58Hz) but some do not (52Hz, 54Hz, etc.)

Some timings have the wrong colors (3840×2160 594MHz has wrong colors but 3840×2160 at 533MHz is good).

I could not get any 5120×1440, 5120×2160, or 5120×2880 timings to work even with refresh rate set as low as 30Hz.

Kind of disappointing. I would expect any timing to work as long as the pixel clock is 600 MHz or less (the limit of HDMI 2.0 at 8 bpc and no chroma sub sampling). It would be cool if it could support higher pixel clock with chroma sub sampling (for example, 4:2:0 can do 1200 MHz with 8 bpc; DisplayPort 1.2 is limited to 4:2:2 which can do 1080 MHz at 8 bpc – good enough for 5K 60Hz).

 

[joevt]

I’ve added my comments about the CAC-1331 to https://insights.club-3d.com/thread/hdmi-to-displayport/

 

[joevt]

One person tried the CAC-1331 with an Xbox One S and an Apple Pro Display XDR and had some issues:
https://forums.macrumors.com/threads/combination-ps4-and-xdr-display.2217347/post-28414320

It may be that the adapter works better with a different display?

[joevt]

[quote author="Jaak Fripont"]
I have my desktop connected to my only display port on my monitor. 
I don’t want to switch cables all the time I want to game with my ps4, is there any solution to this? 
[/quote]
There exist DisplayPort switches or KVMs. The signal is only DisplayPort 1.2 but there also exist DisplayPort 1.4 switches.

[quote author="Jaak Fripont"]
Does this cause any lag? 
[/quote]
It’s converting pixel by pixel. It’s not doing any scaling or other processing so it doesn’t need to see the entire frame before outputing pixels.

[joevt]

I just noticed the Club 3D CAC-1331 HDMI™ to DisplayPort™ 4K60Hz M/F Active Adapter. I’m not sure where to buy it though.

In the second picture, they have the HDMI end connected to a display. That is totally wrong. The first picture showing the PS4, X-Box, and Blu Ray is correct.

[joevt]

It’s missing the 5140×1440 mode. It appears to be missing 2 extension blocks (each is another 128 bytes, total should be 384 bytes). What port was it connected to? What GPU? What cable / adapter? What utility did you use to get the EDID?

Make sure “PBP Mode” is turned off? (it’s more likely that the utility did not grab all the bytes).

Custom Resolution Utility (CRU) utility might be better at getting the EDID.
https://www.monitortests.com/forum/Thread-Custom-Resolution-Utility-CRU

 

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