Does the CAC-1085 allow [email protected] with 4:4:4 ? or does it have to be 4:4:2?
Some early feedbacks from the first guy to have a hand on the adapter ( with a CX 48 )
I quote from Hardforum CX 48 owner thread Page 50 :
Ok – just received and tested stuff for an hour with the CAC-1085 DP1.4 to HDMI2.1 adapter. At this point I CANNOT recommend this product. It’s flawed running on my 2080TI and CX48. This is what i send to Club3d Support:
Just switched back to HDMI – Text is better readable… there is something wrong with the full RGB / HDR that causes text to be fuzzy.
Thats not a fair review – the CX48 only allows 40Gb of bandwidth is not a full HDMI2.1 specs
Running 4K120Hz at 444 RGB 10Bits goes above the possible resolutions the TV allows. The C9 is allowing 48Gb but the new gen TVs from LG from 2020 are limited to 40Gb
Club3D has tested this with the C9, LG could increase to 48Gb with a firmware update – but thats beyond Club3D ability.
Yeah no, i think you’ve been misinformed
Quoted from David Meyer, Ceo of Cedia
• Society of Motion Picture & Television Engineers (SMPTE) Professional member
• Institute of Electrical and Electronics Engineers (IEEE) Professional member
Specialities: Research & interpretation of home technologies, with established speciality in video and connectivity, namely HDR, HDMI interoperability, compliance & bandwidth.
4K @ 120hz 10 bit color uncompressed signal is supposed to be 32.27 Gbit/s
Display Port 1.4 max bandwidth is supposed to be 32.40 Gbit/s using HBR3 (High Bit Rate 3)
So it looks like it fits within the limit, but just…
I don’t know if those limits include data rates or just listing max transmission rates.
I’m guessing it has something to do with this from wiki
Only a portion of DisplayPort’s bandwidth is used for carrying video data. DisplayPort versions 1.0–1.4a use 8b/10b encoding, which means that 80% of the bits transmitted across the link represent data, and the other 20% are used for encoding purposes. The maximum bandwidth of RBR, HBR, HBR2, and HBR3 (6.48, 10.8, 21.6, and 32.4 Gbit/s) therefore transport video data at rates of 5.184, 8.64, 17.28, and 25.92 Gbit/s.
Good news for NVidia 1080TI and LG C9 with this adapter: Somebody on avsforums tried this combination (https://www.avsforum.com/forum/40-oled-technology-flat-panels-general/3123168-2019-lg-c9a-e9-dedicated-gaming-thread-consoles-pc-37.html#post59892538)
And was able to get up to 4k/120Hz/422/10bit. So 120Hz HDR is finally possible, even with an older 1080TI! Altough with reduced 422 color space.
here is the amazon link, available in one week. it was available to order june the 26th but went out of stock so fast that i missed it ….
So my CAC-1085 arrived today. I’m currently using it with a RTX 2080Ti and a LG 55″ SM9000 Nanocell TV (the one equipped with four full bandwidth 48Gbps HDMI 2.1 sockets which also uses the Alpha 7 gen 2 processor – same as the B9 OLED).
The adapter feels very much like a prototype rather than a finished product. I can get 4K 120hz + 8-bit or 10-bit Full RGB color. I can only do 4K 120hz + 12-bit with 4:2:2 chroma sampling. I prefer 4K 120hz 10-bit Full RGB. It seems to give the clearest text and most vibrant colors. There is also no ghosting or motion blurring @ 4K 120hz which is really nice.
The adapter does not support G-sync or Freesync but it does support bog standard V-sync to prevent tearing.
The one huge caveat to this adapter is that its handshake between the graphics card, adapter and TV seems to be very brittle. And what I mean by that is, whenever I switch between HDR to SDR or vice versa, the screen will go black and stay black until I pull the USB power cord out of the adapter and put it back in again.
The same thing happens after I close down a game when i’m finished playing it. The transition from game screen to the desktop screen once again turns the screen black until I power down the adapter and switch it back on again.
It’s really annoying to have to keep on powering it off and on but when it’s working, everything looks so good.
FYI, I’m using a 48Gbps Belkin HDMI 2.1 (2m) cable to connect.
Another thing I noticed is that in SDR mode, I only need to set the TV’s colour setting to 50. But in HDR mode, colours look very washed out until I turn the TV’s colour setting up to 80-85 so that colours pop as much as they do in SDR mode.
For those LG SM9000/B9/C9/CX users out there, in the Picture Settings, I’m using Game Mode and all 4 HDMI sockets have HDMI Ultra HD Deep Color turned on. In the Input Home Dashboard I’ve also edited the HDMI socket hooked up to the Club3D Adapter/GPU to ‘PC Input’.
So After trying the CAC 1085 with C9 and SM9000,it works,
I can get 4k 120 full rgb 12 bits,
But since I dont care about changing from hdr to non hdr or switching resolutions, I dont have the issue that Raven is mentioning.
I keep my tv at 4k sdr at all time. ( Hdr is really overrated imo, it adds input lag and destroy the color accuracy anyway )
I was happy to find that the input lag at 4k 120 on the sm9000 is about 7 ms, which is better than the c9 / cX that will get you 11 ms.