Nvidia GeForce GTX 1660 super and LG 65NANO953NA 8K resolution troubles

[ibanuta]

Hallo ToastyX, congratulations for Your work!
Some two years ago I bought an LG 65NANO953NA tv that is 8k. In september 2020 I got an PC with Nvidia Geforce GTX 1660 Super GPU. I purchased an 8K HDMI 2.1 compliant good quality cable and after long and harsh workaround I succeded to make my PC to "see" my Tv as 8k (active signal resolution: 7680 x 4320), 25 fps.
I tested with an 8k test chart and it was indeed 8k resolution. It worked like this untill some weeks ago. I tried to change the frame rate from 25 to 30 and...from then only troubles. I struggled to come back to 8k but no success. The custom resolution appears 7680 x 4320 but active signal resolution stay at 3840 x 2160 as native.
I can't understand how after more than a year of good working in 8k, now it's impossible to set again that 8k resolution.
Please help me!

[ToastyX]

What was the long and harsh workaround? The GTX 1660 doesn't support HDMI 2.1, so the only way to get 8K @ 24/25/30 Hz is to set the color format to YCbCr 4:2:0.

[ibanuta]

(01-23-2022 04:59 PM)ToastyX Wrote:  What was the long and harsh workaround? The GTX 1660 doesn't support HDMI 2.1, so the only way to get 8K @ 24/25/30 Hz is to set the color format to YCbCr 4:2:0.

How to set the color format to YCbCr 4:2:0? In Nvidia Control Panel, in Windows Display Settings, in Tv Settings, ...? Excuse me, but one time this 8k worked for a long time. I don't know how but it happened? That is why I cannot understand. The same equipment one time works and other time doesn't work.

[ToastyX]

In the NVIDIA control panel where you change the resolution, it should have a color format option.

[ibanuta]

(01-23-2022 06:04 PM)ToastyX Wrote:  In the NVIDIA control panel where you change the resolution, it should have a color format option.

In the NVIDIA control panel, Output color format, only: RGB, YCbCr422 and YCbCr444. What is to be done? Thank You in advance!
P.S. Custom Resolution Utility 1.5.1 reports: Detailed resolution: 3840x2160@60 Hz (594 MHz)[+/+] Name: LG TV SSCR2.
So, it's possibly the TV EDID sent through HDMI cord to GTX 1660 Super be disrupted or something like this?
Normally, the TV EDID should have been 7860x4320@24, 25 or 30 Hz, isn't it?
Should I change (edit) the EDID?

[ToastyX]

(01-23-2022 06:14 PM)ibanuta Wrote:  In the NVIDIA control panel, Output color format, only: RGB, YCbCr422 and YCbCr444. What is to be done? Thank You in advance!
P.S. Custom Resolution Utility 1.5.1 reports: Detailed resolution: 3840x2160@60 Hz (594 MHz)[+/+] Name: LG TV SSCR2.
So, it's possibly the TV EDID sent through HDMI cord to GTX 1660 Super be disrupted or something like this?
Normally, the TV EDID should have been 7860x4320@24, 25 or 30 Hz, isn't it?
Should I change (edit) the EDID?

The EDID is fine. 8K would be in the extension block. Export a file using CRU and post it here so I can take a look.

[ibanuta]

(01-23-2022 08:25 PM)ToastyX Wrote:  

(01-23-2022 06:14 PM)ibanuta Wrote:  In the NVIDIA control panel, Output color format, only: RGB, YCbCr422 and YCbCr444. What is to be done? Thank You in advance!
P.S. Custom Resolution Utility 1.5.1 reports: Detailed resolution: 3840x2160@60 Hz (594 MHz)[+/+] Name: LG TV SSCR2.
So, it's possibly the TV EDID sent through HDMI cord to GTX 1660 Super be disrupted or something like this?
Normally, the TV EDID should have been 7860x4320@24, 25 or 30 Hz, isn't it?
Should I change (edit) the EDID?

The EDID is fine. 8K would be in the extension block. Export a file using CRU and post it here so I can take a look.

The .exe file isn't allowed as attachment.
This the .bin exported file.

---

I posted an exported file from CRU in the previous reply.

[ToastyX]

The TV already defines 7680x4320 @ 24/25/30/50/60 Hz with YCbCr 4:2:0 in the extension block, so 8K should work automatically if the video card supports it. What did you do before to make it work? As far as I know, the GTX 1660 doesn't officially have a way to support 8K with HDMI.

Maybe it will work if I define the 4:2:0 resolutions a different way. Try importing this:
  LG-8K.bin (Size: 256 bytes / Downloads: 358)

[ibanuta]

(01-24-2022 01:32 PM)ToastyX Wrote:  The TV already defines 7680x4320 @ 24/25/30/50/60 Hz with YCbCr 4:2:0 in the extension block, so 8K should work automatically if the video card supports it. What did you do before to make it work? As far as I know, the GTX 1660 doesn't officially have a way to support 8K with HDMI.

Maybe it will work if I define the 4:2:0 resolutions a different way. Try importing this:

I imported but the active signal remained 3840 x 2160.
What did I do before to make it work? That was a year ago.
First of all, I'm not an IT specialist. I've been trying a lot of settings in Nvidia Control Panel, Display settings and in LG TV settings with the remote control. At one point, I simply noticed that the desktop appeared in 8k resolution. That is, at 100 scaling, the text was no longer fuzzy. Although it was very small, it was clear.
Then I wanted to make sure it was 7860 x 4320 and I put a 7860 x 4320 chart from YouTube (TobyFree 8k ...something like this). Indeed the vertical and horizontal 1 pixel lines and 1 px chess images were OK. It wasn't until I lost that 8k resolution that I noticed that the Active signal resolution was no longer 7680 by 4320 but 3840 by 2160. And, of course, on the 8k chart those 1 px images were no longer separated but united. Only the other 2 pixel images were still separated. Simply!
I panicked, considering that for a year I used the PC at 8k resolution on my LG 8k TV with HDMI. I kept struggling but I was not lucky enough to catch that 8k resolution. After about 2 days I resorted to restoring the computer to a previous date when 8k was working. I wasn't very good at it and I ruined the Windows.
I took the computer to a former colleague and he reinstalled the Windows 10.
I tried all sorts of settings again but without success. Now I'm trying to study in more depth how the GPU works with the TV. It's pretty complicated for me but I bought that 8k TV and I have to use it to its capacity.
I complicated my life but maybe it's more interesting and even more beautiful.
I hope to succeed in the end. That with the help of people like You!

[ToastyX]

I honestly don't know how you did it because if the GPU supported 8K with HDMI, it would have worked out of the box without any tweaking.

In the NVIDIA control panel in the "Change resolution" section, make sure the color depth is set to 8 bpc. Then check if the YCbCr 4:2:0 color format is available.

If not, try importing this:
  LG-8K-2.0.bin (Size: 256 bytes / Downloads: 277)
That's with the HDMI 2.1 stuff removed. If that doesn't work, then I have no idea.