Question New LG C4, getting more than 60hz, infuriating

[blueangel42]

I cant, for the life of me, get higher than 4k 60hz on my new C4 display. I was easily able to get this to work, as my current set up is, on my 2023 Samsung S90C; 4k 120hz.

I have done a lot of searching, and I think this is going to come down to someone confirming my suspicion that the C4 refuses to play nice with Display Port to HDMI adaptors. But I am no expert and really just learned alot about different HDMI / DP capabilities over the last 3 hours.

I am using such an adaptor, coming out of my 5700xt graphics card (DP 1.4a, capable of 4k 120hz, at least through DSC), going into a 35ft HDMI 2.1 cable, into my C4 display. Both these adaptors are 8k 60hz / 2.1 hdmi "ultra bandwidth" compatible

This hardware setup works flawlessly on my 2023 S90C, all I have to do is make sure Game Mode is on, and BOOM, 120hz works.

For some ungodly reason, this does NOT work with my new 2024 LG C4. I cant get more than 4k 60hz. I think it has something to do with the C4 not liking my display port output, even though I am using an HDMI adaptor.

has anyone else had this issue?

I have 2 videos showing my issue:

works on S90C

no work on C4

 

[COLGeek]

Drop the adapter. That is likely the issue.

 

[blueangel42]

but i need the adaptor! My graphics card's HDMI outs only support 4k 60hz, but the display port out supports higher with DSC

 

[COLGeek]

Those adapters typically only meet the standard speeds.

 

[blueangel42]

What standard? the adaptor solution i have is working fine putting out 4k 120hz to my Samsung

Is there another way i can trick my c4 into thinking its getting what it needs? like a true DP to HDMI converter?

 

[BFG-9000]

Well there sure was a way but your card is a generation too new.

So you could look for a utility that does the same for RDNA cards.

 

[COLGeek]

What standard? the adaptor solution i have is working fine putting out 4k 120hz to my Samsung

Is there another way i can trick my c4 into thinking its getting what it needs? like a true DP to HDMI converter?

By standard, I was referring to the typical standard 30/60hz speeds.

You can see if there are specific drivers for your TV and install those on your PC.

https://www.lg.com/us/support/software-firmware-drivers

 

[geofelt]

I think it is time to upgrade your graphics card to one that is capable of hdmi 2.1 output.
A stronger card is good for 4k gaming regardless.
I had the same problem with a GTX1080 and an upgrade to rtx3070 solved it.
I tried adapters also that did not work.

 

[blueangel42]

I think it is time to upgrade your graphics card to one that is capable of hdmi 2.1 output.
A stronger card is good for 4k gaming regardless.
I had the same problem with a GTX1080 and an upgrade to rtx3070 solved it.
I tried adapters also that did not work.

Your correct, it is!
my new computer parts are coming in with a 9800 x3d, finally after 11 years. I have a 4790k i7 currently powering my 5700xt.

Whats holding me back is, I'm holding out for the 5090 which is not until January, allegedly.

I have been considering an RX 6700 to hold me over till then, but im on the fence:
My current cpu / mobo / case will become a second computer in the house and at that point i dont care if its capped at 4k 60hz

While my 5700xt seems to be treated well by the 4790k, (i do get 60-120hz in older games), if i upgrade to the RX 6700 (non xt), will I get bottleneck? i have seen that the 6700 uses all 16 pci lanes, so it should be alright on my pci 3.0 mobo...
Im spending so much money on my top tier setup, its hard to justify yet dropping not just a 200$ graphics card, but a 5700 x3d (or something) and a mobo for it, and RAM, and a new cooler for a "guest" gaming computer (doubt my 2014 corsair AIO will fit it, such a trooper)

In a perfect world i would just keep my 5700xt and pop it back in my old computer once my new one gets its 5090

What would you guys do? stick it out till Jan, get a hold-over cheap graphics card, try to trick the C4 to accept the DP 1.4a signal some how,

 

[blueangel42]

also i figured it out the root of my problem; my 1.4 DP to 2.1 HDMI adaptor is *not compatable with LG C2 (and there for C4) TV's!
LAME
https://www.amazon.com/UANTIN-Displ...2.1+adapter+with+4k+144hz,aps,118&sr=8-7&th=1

If i can just find one that IS compatable with LG tv's? or is the C series just inharently unable to accept any converted signal?
I dont understand why LG specifically is incompatable but others like my S90C are

 

[blueangel42]

I FREAKING DID IT
what you have to do is follow instructions on this youtube video

View: https://www.youtube.com/watch?v=FKRh6IZuW-M&list=LL&index=2&t=7s

you change pixel format to YCbCr 4:2:0

Once i did that i tried to be a hero and see if other slightly better ones would work, and doing that BORKED everything. Computer would no longer connect to C4. Had to switch to S90C to change it back, and it was STILL borked. WHich was stupid, since i didnt change any other variable. So i reset my 5700xt to factory settings, and reset C4 to factory settings.
then i had issue where i could not enable deep color... that took hours. so stupid. finally think i figured out how to get that enabled again, i had to disable OFF and /or enable FreeSync (which my graphics card does not even support apparently) and doing so let me turn on game mode and in turn deep color.
from there, i changed pixel format back to the above 4:2:0
and can set to 120hz without losing signal. it works fine now.

This can hold me over till the 5090 comes out and i can get HDR back.

I hope this helps someone out in the future!!!

what you guys think?

 

[geofelt]

Graphics cards sell for what they are worth.
If the 5090 card is so over the top, you can expect to see a big retail price on it, and hard to find one.
Then also the early adopters will par over retail to get one.
It may be smarter, if you have a budget, to point towards something below top dog.

 

[blueangel42]

ive been saving up 1.2k just in amazon prime $ over the years for this exact purchase, i can do more to bring it up to where it needs to be.
I wont pay more then msrp though, so the hardest part will be figuring out how quickly i can lock one down once they release, ive never had to fight bots / tons of other early adopters for a graphics card

 

[Glenwing]

I FREAKING DID IT
what you have to do is follow instructions on this youtube video

View: https://www.youtube.com/watch?v=FKRh6IZuW-M&list=LL&index=2&t=7s

you change pixel format to YCbCr 4:2:0

Once i did that i tried to be a hero and see if other slightly better ones would work, and doing that BORKED everything. Computer would no longer connect to C4. Had to switch to S90C to change it back, and it was STILL borked. WHich was stupid, since i didnt change any other variable. So i reset my 5700xt to factory settings, and reset C4 to factory settings.
then i had issue where i could not enable deep color... that took hours. so stupid. finally think i figured out how to get that enabled again, i had to disable OFF and /or enable FreeSync (which my graphics card does not even support apparently) and doing so let me turn on game mode and in turn deep color.
from there, i changed pixel format back to the above 4:2:0
and can set to 120hz without losing signal. it works fine now.

This can hold me over till the 5090 comes out and i can get HDR back.

I hope this helps someone out in the future!!!

what you guys think?

Well, this avoids the problem rather than solving it; 4:2:0 subsampling reduces the resolution of the color components to 1080p thus reducing the bandwidth by half. So you can select 120 Hz rather than 60 Hz with the same bandwidth. The same "trick" can be used to run 4K 120 Hz on HDMI 2.0 instead of 4K 60 Hz. But of course, you're sacrificing image resolution.

It's interesting to me that LG TVs specifically are incompatible. But hard to say who's fault it is. My suspicion would be the adapter is not quite up to spec, and the Samsung just has looser requirements than LG. Or perhaps chroma subsampling is just enabled by default on that one.