LocutusHUN
So i have some problems. Upgraded from my B8 to CX.
 
Bought an AQ Pearl 48 cable, 1.5m. As it is written in the 1st post, that it should work.
 
Now i can set up 4K/120Hz/HDR/10bit/Gsync: Ocassional flickering on desktop.
Ok, lets disable gsync: Still flickering, but much rare.
Tried to go back to 4K60: No signal. Screen is black, and whatever i do, it wont come back.
Reset. No signal. Not even post screen appears, but judging from the peripherials windows boots up normally, there is just no display.
Turned off pc. Turned on again: there is signal again. Seems to work ok, no flickering at 4K120 now.
If i try to turn on gsync, it begins to flicker very intesively. Also, any resolution change results in black screen, and then i have to turn off pc.
 
Could my cable be wrong? Or what the hell is this?

Hey i am running a bx 55 with a xc3 ultra 3080 newest drivers and newest x1 and havent had any issue watching twitch,youtube,gaming i did notice with newest nv driver some games took a mhz drop on gpu and others are doing much better. poe worse/bo coldwar much better.That is with 4K/120Hz/HDR/10bit/Gsync 2 monitor one lg oled///other samsung 1080 60hz all using this cable https://www.amazon.com/gp/product/B07WNM2NJ5/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1 I allso have tried many but this one for the price seems the best so far.

PhantomApollyon
Update: Turning OFF Windows's fast startup corrected my one outstanding issue with literally no noticeable change to the speed of the machine starting up.
 
System > Power & Sleep > Additional power settings > Choose what the power buttons do > Change settings that are currently unavailable > uncheck "Turn on fast startup (recommended)"

This is what I had to do for the one startup problem I had for my 3090 and 48" LG CX. Before I made this change I pressed my PC power button and the computer would turn on, but nothing would happen on-screen. I had to do a hard shutdown and then restart again and it would work. This was fixed by turning off fast startup- now it starts properly every time.

my 3090 works great for the lg cx 48 so far. 

Do you guys recommend using default color settings or force Nvidia color settings. I have my CX set to PC mode and Game mode. At the moment i'm using default color settings and the TV seems to run 8 bit and switches to 10 bit when running turning HDR on in Windows 10. I just want to figure out the best settings between the 3090 and CX for least amount of color banding(I notice it when looking into skies in games).
 
Also, i've been trying to figure out why when installing Dolby Access to use Dolby Atmos for Home Theater in Windows 10, it breaks sound for stereo and 5.1(no audio at all). 7.1 has a problem where audio pops in and out constantly. Atmos plays fine, until it randomly stops working. I'm able to get it working again(sometimes) by playing another audio/video file. So I uninstall Atmos for now and use 7.1 since 5.1 doesn't have rear channel audio. Forgot to mention i'm running my PC>CX>HW-Q80R soundbar via eARC. TV is set to passthrough and bitstream with bypass enabled. I reached out to support for Dolby Access and they said people with soundbars that use Cirrus Logic are having issues with it right now so I guess it's something that might get fixed down the road. Sorry for my long post guys!

kring
This original post will continue to be updated with more information we learn as 3080/3090's get into the hands of gamers who have 4K@120hz monitors.  It started with the LG OLED CX, but I think it's best to open it up to any good information people have to share and may help the community.  The key here is the 4K@120hz,  60hz is half the bandwidth and won't experience any of the challenges.
 
General suggestions for any 4K@120hz users:

1. You may need to cut out a rear slot divider from your case if it blocks airflow (Other cards also needed this done) it's because this is a dual slot card.
2. Default bios switch is set to stock, so I recommend flipping to OC for FTW3 users with duel bios
3. Updated to latest drivers, 456.71 fixed a lot of issues with stuck clock
4. Update Precision X1 to 1.1.0.11 which will also apply a firmware update (unless new cards are already coming updated)
5. HDMI cable needs to be 8K 48gbs supported or you will get issues.  Windows looks fine but stuck at 60hz, some games crap out i.e. RDR2 when maxed.  These are actually really hard to find. I went with one from Walmart - Monster 8K 15ft 48gbs platinum fiber optic HDMI for $45.00 and it does NOT work for everything so I DON'T Recommend this cable.  I have a monoprice 8K cable and so far it's doing everything. the issues I had with the monster cable are gone.
6. Set Windows Display capabilities - go into advanced display settings and set resolution to 3840 x 2160, you also have to set the monitor Refresh to 120hz (defaults to 30 or 60), and enable HDR, Enable Variable refresh rate, enable hardware-accelerated GPU scheduling (though this does rob a few cycles of the GPU)...  It's amazing none of this is on by default or auto-detected.  would be nice if LG offered a driver!
7. Set Nvidia Control Panel display settings - from the Nvidia control panel choose Change resolution, in section 2 - choose a resolution of "PC"  3840 x 2160, 120hz refresh. Section 3, override to NVIDIA color settings and choose 32-bit, 10 bpc, RGB, FULL. and apply
8. Set Nvidia Control Panel video playback settings - Nvidia Control panel, chose video\Adjust video color settings on left tree menu, then choose "with the NVIDIA settings", select the advanced tab, and choose "Full" so video's use the full black level HDR capabilities.
9. Set Nvidia Control Panel scaling option -in Nvidia control panel, choose Adjust desktop size & position from left tree menu,  for scaling it seems to look best when set to No scaling or aspect ratio, scale on display so it's all native signal to the TV and it handles any adjustments.
10. Set Nvidia Control Panel G-sync -in Nvidia control panel and all your games MUST have VSYNC off, or it will clamp it low, for me I had a few that were stuck at 60hz wth v-sync on, some let it go to 120, but locking v-sync on defeats the purpose of having G-sync.  Makes sure G-sync is enabled on your display as well!
11. If you have any trouble getting any settings to stick, there's a really high chance your problem is your HDMI cable not supporting a full 48gbs, I tried 4 different newer high quality cables that were 4K rated and NONE of them worked.

 
Suggestions for OLED CX, C9 users:

1. Update your TV Firmware to 03.11.25 or newer which fixes a few issues like g-sync flickering.  there is a 03.11.26 out there but it's for 55", 65" models only
2. For LG OLED TV specific settings.
   1. Set the HDMI input to Console (or PC) via the main home screen edit which supposedly is optimized for PC/Console.
   2. Under all settings \ picture, set aspect ration to 16:9, turn off energy savings,
   3. Under the additional settings make sure HDMI Ultra HD Deep color is enabled, Instant gaming response is enabled, turn off filmmaker mode auto change. 
   4. Under the Picture mode keep sharpness <10, any higher creates artificial film grain look.
   5. Under Advanced controls menu I turn off dynamic contrast, dynamic tone make to HGIG, Super resolution off, color gamut to auto. 
   6. Under Picture options menu I set black level to low, motion eye care to off.
   7. Under OLED screen saver menu, I leave on Screen Shift, but turn off Logo luminance Adjustment.
   8. Under the General \ AI Services - turn off AI Picture pro, AI brightness control and then under additional settings turn off power saving mode.

 
REQUEST from Community: We are finding that many issues are due to HDMI cables.  so we're going to get a listing going of what cables work and dont, so people know what to order and don't waste money or deal with frustration.  Please share your specific cables that are working or not working and I'll update the OP.  For it to be "Working" it means ZERO issues. every game works, windows runs 4K full color with 32-bit 10 bpc @ 120hz,  there is never any flicker, all games launch FULLSCREEN and run without issues, artifacts.

Signs of cable failure: Unable to reach full windows resolution @ 120hz, games only run in windowed/borderless but not full screen, there is flickering or occasional black screens, games crash or failing to start. Some games worked fine, but most have trouble, like SW Battlefront II won't go into full screen, RDR2 crashes on anything over 2560 res, Death Stranding had some visual artifacts and at one point screen went green & pink. other games were not getting over 60 FPS when I know it can. 

Working:

• Monoprice DynamicView Ultra 8K Premium High Speed HDMI Cable, 48Gbps, 8K, Dynamic HDR, eARC, 6ft Black - Product # 31231 - confirmed on LG CX with 3090
• Belkin HDMI Ultra High Speed - Product # AV10176bt1M-BLK or AV10175bt2M-BLK - confirmed on LG CX with 3090
• AudioQuest Pearl 5' 8K-10K 48Gbps HDMI Cable (From Best Buy)

 
Partially Working:  (meaning it appears to be working, but there may be an anomaly you are not sure it's 100%)

• Monoprice 138627 Ultra High Speed HDMI Cable - 30 Feet - Black, 8K@120Hz, Dynamic HDR, 48Gbps, Fiber Optic
  • Workaround is to turn "Instant Game Response" mode OFF and then back ON before playing a game to get G-sync to work properly, everything else works perfectly fine.  This is the only known long optical cable found that works.  this was with LG OLED, so it's possibly issue with IGR/Firmware of the TV and not the cable.

 
Failed:

• Monster UHD Platinum Fiber Optic HDMI Cable - 15ft - VIPRB-HDMI700HD4M 
  • Full Screen RDR2 fails on Vulkan, Tomb Raider Crashes at launch.
• AmazonBasics Nylon-Braided 4K, 18Gbps HDMI to HDMI Cable, 10 Feet
  • No 4K 120hz Desktop resolution, no games run 4K
• 4K HDMI Cable 10 ft - Atevon High Speed 18Gbps HDMI 2.0 Cable - HDCP 2.2-4K HDR, 3D, UHD 2160P, 1080P, Ethernet - 28AWG Braided
  • No 4K 120hz Desktop resolution, no games run 4K
• Twisted Veins HDMI Cable 8 ft, 2-Pack, Premium HDMI Cord Type High Speed with Ethernet, Supports HDMI 2.0b 4K 60hz HDR
  • No 4K 120hz Desktop resolution, no games run 4K
• Generic HDMI cables
  • Mixed results but none of them worked for games, only a few let windows run 120hz.

 
I got my 55" CX last night. I had a 18GBps loooooong HDMI which works for 4k60
Blackweb Premium 4K HDR HDMI Cable, 50' - Walmart.com - Walmart.com
It def doesn't do gsync, HDR, or 120Hz. My JS9000 was Samsung's Crystal View, so proto-HDR. 
 
My Zeskit arrives Monday. It's nice to have a reason to finally browse through this thread!
 

A new bios has been released - it's on the Korean site which is compatible with  US models, but not UK models.   version is 3.21.09
 
this has a lot of little fixes - VRR, flicker @ 120hz, G-sync better compatibility.  I've been using for a few days and it's been working great... so upgrade, or wait till it it's real soon via the TV.
 
https://www.lgservice.co....6%B4_OLEDxxCXX_GXX_O20

kring
A new bios has been released - it's on the Korean site which is compatible with  US models, but not UK models.   version is 3.21.09
 
this has a lot of little fixes - VRR, flicker @ 120hz, G-sync better compatibility.  I've been using for a few days and it's been working great... so upgrade, or wait till it it's real soon via the TV.
 
https://www.lgservice.co....6%B4_OLEDxxCXX_GXX_O20

Might be a dumb question, but how do you load this for upload. USB stick?
I'm new to WebOS after years of Tizen.
 

DarkTAO
 
Might be a dumb question, but how do you load this for upload. USB stick?
I'm new to WebOS after years of Tizen.

The English version of the instructions, which apply for the folder name and formatting, are on the English site and are here: http://gscs-b2c.lge.com/downloadFile?fileId=h2cls7CAEBj7NelO2lCwkw 

arestavo

DarkTAO
 
Might be a dumb question, but how do you load this for upload. USB stick?
I'm new to WebOS after years of Tizen.

The English version of the instructions, which apply for the folder name and formatting, are on the English site and are here: http://gscs-b2c.lge.com/downloadFile?fileId=h2cls7CAEBj7NelO2lCwkw 

Thanks, that did it. 
 
Really like that the thing instantly recognized the update and started the process as soon as the USB was installed.
 

kring
A new bios has been released - it's on the Korean site which is compatible with  US models, but not UK models.   version is 3.21.09
 
this has a lot of little fixes - VRR, flicker @ 120hz, G-sync better compatibility.  I've been using for a few days and it's been working great... so upgrade, or wait till it it's real soon via the TV.
 
https://www.lgservice.co....6%B4_OLEDxxCXX_GXX_O20

 
How do i download something from this mess?
I assume the lower 2 are the download links, but wich one, and why isnt anything happening if i click on them?