LG B9 OLED and Legion 5 RTX 3070

[Kirky2k15]

Can't get 4k 120hz working at all - tried 2 48gbps rated cables from different manufactures one is the club 3d one that every forum says works.

 

HDR doesn't work at all on any resolution

 

best I can get is 4k 60

 

Anything higher than that results in black screens

 

I've tried with and without gsync enabled

 

I bought this lenovo legion 5 with RTX 3070 specifically to use with my b9 oled at 4k 120hz with HDR and GSYNC enabled but so far I cannot do that.

 

Obviously I've got the latest drivers and firmware installed on everything - this isn't my first time troubleshooting something

 

Does any one have any suggestions for what I can try before I give up completely?

 

Thanks

[porina]

Ooh, I have same laptop and TV, but I've never tried it.

 

Without trying it, are you using it in dynamic or discrete graphics mode? I'd guess you'd need the latter for any chance of it working. I'll try it myself in a moment.

[Kirky2k15]

I'm in discrete mode (non hybrid mode in vantage software) one of the first things I did when I bought the laptop was disable hybrid mode as it seriously gimped the performance of the 3070

[Home Theater Dummy]

Are you connecting directly to your TV's  input or are you running through a receiver. You may need to set to "ENHANCED" under the 4k settings.

Also Set TV settings to PC mode. LG B9 should support 10 bit 4:4:4 over HDMI but Its possible that NVIDIA does not? What I can find say that it should... but maybe if its laptop card 10bit color could not be supported maybe change to 8bit? I am seeing in the past NVIDIA placing an artificial limit to 60 hz over HDMI 2.1 so this may be your issue?

[porina]

Just tried it, and it is working for me. Note I didn't try any content on it, but Windows was reporting things as expected.

 

After setting it to extend and not duplicate I could switch it to the following modes:

1, 4k, 60 Hz, SDR 8-bit (default when plugged in)

2, 4k, 120 Hz, SDR 8-bit

3, 4k, 60 Hz, HDR 10-bit

4, 4k, 120 Hz, HDR 8-bit dithered

 

When HDR was on it looked really bright and saturated on desktop. I forgot to check G-sync status.

[Kirky2k15]

1 minute ago, porina said:

Just tried it, and it is working for me. Note I didn't try any content on it, but Windows was reporting things as expected.

 

After setting it to extend and not duplicate I could switch it to the following modes:

1, 4k, 60 Hz, SDR 8-bit (default when plugged in)

2, 4k, 120 Hz, SDR 8-bit

3, 4k, 60 Hz, HDR 10-bit

4, 4k, 120 Hz, HDR 8-bit dithered

 

When HDR was on it looked really bright and saturated on desktop. I forgot to check G-sync status.

Thanks for checking, yeah that's the really strange thing, I can't set it to duplicate, it only works when I set it to extend, are you setting your settings via windows or via the nvidia control panel

 

Note I'm connected straight from laptop's hdmi port to port 3 on my tv - note all 4 hdmi ports on the b9 are rated hdmi 2.1 so should support 4k 120hz with hdr

 

One thing I do need to try is to unplug every other HDMI device that's plugged into my TV to see if that does anything.

 

I've got Virgin TV and an Android TV box connected so will unplug those and try again.

[porina]

1 minute ago, Kirky2k15 said:

Thanks for checking, yeah that's the really strange thing, I can't set it to duplicate, it only works when I set it to extend, are you setting your settings via windows or via the nvidia control panel

Mine defaulted to duplicate when I first plugged it in. I'm setting in Windows only. Wonder if it could be a firmware thing. I think I've updated both laptop and TV firmware within the last couple months or so. In fact I found the USB stick still in the TV! I was wondering where that went as I use it for OS installs too.

 

BTW I just went back to check G-sync. According to NV control panel, G-sync is enabled for 120 Hz in both SDR and HDR. Again, I didn't test it beyond that.  

 

1 minute ago, Kirky2k15 said:

Note I'm connected straight from laptop's hdmi port to port 3 on my tv - note all 4 hdmi ports on the b9 are rated hdmi 2.1 so should support 4k 120hz with hdr

 

One thing I do need to try is to unplug every other HDMI device that's plugged into my TV to see if that does anything.

 

I've got Virgin TV and an Android TV box connected so will unplug those and try again.

My usage is kinda similar. I have a PS4 on input 1, and a 3070 desktop on input 2. My testing was on input 3, which I had to steal from my Switch. I don't think unplugging others should make a difference.

 

Have you otherwise proven the cable is good? I know you said you tried two cables, so it seems less likely to be the problem.

[Kirky2k15]

Getting somewhere - I can now set 120hz at 2560x1440 if i set it via the nvidia control panel, note for some reason the resolution settings in here are confusing as you have a choice of ultra hd, hd and sd then you have the pc resolutions which are separate - I've set it to 1440p 120hz using the pc resolutions and the yCbCr is set to 444 8bpc, will play around with these a bit more but so far setting to 4k 120hz is still not possible.

 

here's links to the 2 cables I've got:

 

https://www.amazon.co.uk/gp/product/B07H5Y5N55/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

 

https://www.ebay.co.uk/itm/392421257263?var=661421182604

 

Note both are 2m as I was advised not to go over this due to signal degradation 

[porina]

Good luck. For reference, the cable I used for laptop testing just now is: https://www.amazon.co.uk/gp/product/B098JLTX4W/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

 

And the one I use with the desktop 3070 is: https://www.amazon.co.uk/gp/product/B08NW61F92/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

[Kirky2k15]

6 minutes ago, porina said:

Good luck. For reference, the cable I used for laptop testing just now is: https://www.amazon.co.uk/gp/product/B098JLTX4W/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

 

And the one I use with the desktop 3070 is: https://www.amazon.co.uk/gp/product/B08NW61F92/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Cheers, looks like I'll have to buy those 2 because no matter what I do I can't get higher than 4k 60 with HDR 444 only 8bpc - anything higher than this results in blank screens.

 

Does that indicate a bad cable?

 

I note the amazon reviews on the club 3d one are mixed some saying it is 48gbps some saying its not?

[Stagea]

1 hour ago, Kirky2k15 said:

Thanks for checking, yeah that's the really strange thing, I can't set it to duplicate, it only works when I set it to extend, are you setting your settings via windows or via the nvidia control panel

 

Note I'm connected straight from laptop's hdmi port to port 3 on my tv - note all 4 hdmi ports on the b9 are rated hdmi 2.1 so should support 4k 120hz with hdr

 

One thing I do need to try is to unplug every other HDMI device that's plugged into my TV to see if that does anything.

 

I've got Virgin TV and an Android TV box connected so will unplug those and try again.

What laptop are you running? If it has AMD or Intel graphics together with your dedicated GPU, then there is a big chance that it's using the integrated GPU for the output. That's how the majority of laptops work, as this allows the system to switch between integrated and dedicated graphics.

[Kirky2k15]

7 hours ago, Stagea said:

What laptop are you running? If it has AMD or Intel graphics together with your dedicated GPU, then there is a big chance that it's using the integrated GPU for the output. That's how the majority of laptops work, as this allows the system to switch between integrated and dedicated graphics.

Thanks but we've already been over this in the thread, if you read it back it says that I've got a Lenovo Legion 5 with an RTX 3070 laptop GPU which is in discrete graphics mode - not hybrid mode or anything.

[Kirky2k15]

Also the Club 3d cable I'm using has got a QR code on the box which I've scanned and takes you to google play store to download the HDMI checker app - this confirms the cable I've got is certified for up to 8k60hz so its pretty much not the cable unless it is defective like in Linus' latest video - my tv is running the latest firmware and have the latest drivers from nvidia - I don't have a $100000 HDMI cable tester to hand though and I don't have anything else lying around that will output 4k120hz EG ps5 xbox etc

[Want10bitOledPC]

Hey, I have a similar situation - Legion 5 pro with 3070 and an LG C9 and LG C1, I tried 3 cables and the most I got is 120hz 4k at 8bit 4:4:4 (but I use RGB).

10bit is probably not possible due to lenovo gimping their ports to be way under heir optimal bandwidth... not sure what the HDMI 2.1 is, but my guess 32Gb/s or less.

Wish I knew this before hand, it seems other laptops with hdmi 2.1 has no such issues.