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LG OLED Freesync Mod (tested on 55" B9 Series)

R-T-B

R-T-B

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System Name Pioneer
Processor Ryzen 9 9950X
Motherboard MSI MAG X670E Tomahawk Wifi
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Storage Intel 5800X Optane 800GB boot, +2x Crucial P5 Plus 2TB PCIe 4.0 NVMe SSDs, 1x 2TB Seagate Exos 3.5"
Display(s) 55" LG 55" B9 OLED 4K Display
Case Thermaltake Core X31
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To make this brief: LG's famous line of OLED displays are "Gsync compatible" over hdmi, meaning they are really just freesync displays in disguise. Despite this, they do not work on AMD graphics cards out of the box, because LG has blatantly neglected to add the EDID information Freesync expects to find. Fortunately, this info can be readded with a nice little tool : CRU (Custom Resolution Utility). Link.

The following visual illustrates how this is done. Note the B9 OLED panel has a native gsync range of 40-60 hz and thus does not enable LFC, however in my experience you can use a timing of 30 hz on the low end and thus enable LFC and the display accepts it fine. I have tested this on my panel and at least on it, the LFC works flawlessly and I basically get Freesync Premium. YMMV.

Here's the basic visual guide. Please feel free to ask if you have any questions, I am off enjoying the fruits of my latest purchase.

1.png

1.png

2.png

3.png

4.png


Now OK-out, Reboot, and:
Freesync.png

Timings.png


FYI: You will need to repeat this guide each driver reinstall.

A quick edit / note:

The 30hz setting did indeed enable LFC on my panel, but it caused some random black screen issues at some point in that range I could not tolerate. As such, you may have to use the stock range of 40-60hz to get good results. I certainly did, sadly. This will disable LFC, but you still get something.
 
R-T-B said:
To make this brief: LG's famous line of OLED displays are "Gsync compatible" over hdmi, meaning they are really just freesync displays in disguise. Despite this, they do not work on AMD graphics cards out of the box, because LG has blatantly neglected to add the EDID information Freesync expects to find. Fortunately, this info can be readded with a nice little tool : CRU (Custom Resolution Utility). Link.

The following visual illustrates how this is done. Note the B9 OLED panel has a native gsync range of 40-60 hz and thus does not enable LFC, however in my experience you can use a timing of 30 hz on the low end and thus enable LFC and the display accepts it fine. I have tested this on my panel and at least on it, the LFC works flawlessly and I basically get Freesync Premium. YMMV.

Here's the basic visual guide. Please feel free to ask if you have any questions, I am off enjoying the fruits of my latest purchase.

View attachment 156333
View attachment 156333
View attachment 156335
View attachment 156336
View attachment 156337

Now OK-out, Reboot, and:
View attachment 156338
View attachment 156339

FYI: You will need to repeat this guide each driver reinstall.

A quick edit / note:

The 30hz setting did indeed enable LFC on my panel, but it caused some random black screen issues at some point in that range I could not tolerate. As such, you may have to use the stock range of 40-60hz to get good results. I certainly did, sadly. This will disable LFC, but you still get something.
Click to expand...
Excellent comment. It is also possible to export the configuration if you need it in the future.

R-T-B said:
To make this brief: LG's famous line of OLED displays are "Gsync compatible" over hdmi, meaning they are really just freesync displays in disguise. Despite this, they do not work on AMD graphics cards out of the box, because LG has blatantly neglected to add the EDID information Freesync expects to find. Fortunately, this info can be readded with a nice little tool : CRU (Custom Resolution Utility). Link.

The following visual illustrates how this is done. Note the B9 OLED panel has a native gsync range of 40-60 hz and thus does not enable LFC, however in my experience you can use a timing of 30 hz on the low end and thus enable LFC and the display accepts it fine. I have tested this on my panel and at least on it, the LFC works flawlessly and I basically get Freesync Premium. YMMV.

Here's the basic visual guide. Please feel free to ask if you have any questions, I am off enjoying the fruits of my latest purchase.

View attachment 156333
View attachment 156333
View attachment 156335
View attachment 156336
View attachment 156337

Now OK-out, Reboot, and:
View attachment 156338
View attachment 156339

FYI: You will need to repeat this guide each driver reinstall.

A quick edit / note:

The 30hz setting did indeed enable LFC on my panel, but it caused some random black screen issues at some point in that range I could not tolerate. As such, you may have to use the stock range of 40-60hz to get good results. I certainly did, sadly. This will disable LFC, but you still get something.
Click to expand...
On my 60Hz furreca monitor, I was able to enable 75Hz in some resolutions. :D:D:laugh::laugh:
 
Yep, in short because of being a VESA spec, a lot more displays support freesync than advertise it. :)

Johnny05 said:
I do the same thing on my C9 with 40-60hz. I can't go back after getting use to freesync.
Click to expand...

Good to hear the extra picture processing on the C9 does not get in the way of the mod. You really are getting the best of all worlds there!
 
R-T-B said:
Yep, in short because of being a VESA spec, a lot more displays support freesync than advertise it. :)



Good to hear the extra picture processing on the C9 does not get in the way of the mod. You really are getting the best of all worlds there!
Click to expand...


Hey and thanks a lot for this guide.

I'm also debating getting an AMD GPU to go with my LG B9. I wonder though, if I want to play high refresh rate (up to the 120Hz the LGB9supports), should I input 40 - 120 Hz in the range limit instead of 40-60?
 
doich said:
Hey and thanks a lot for this guide.

I'm also debating getting an AMD GPU to go with my LG B9. I wonder though, if I want to play high refresh rate (up to the 120Hz the LGB9supports), should I input 40 - 120 Hz in the range limit instead of 40-60?
Click to expand...

40-120 would be appropriate only if you can send it. You'd need an hdmi 2.1 gpu, or run a lower res.
 
Last edited:
I forgot how sweet CRU was that tuned my QNIX 2710 quite nicely.
 
R-T-B said:
40-120 would be appropriate only if you can send it. You'd need an hdmi 2.1 gpu, or run a lower res.
Click to expand...


Yeah, I'm looking at the new AMD GPUs (RX 6800 XT), once they're actually in stock of course.

Those have HDMI 2.1 and can easily run games in 120HZ 1440p from what I've seen.
 
doich said:
Those have HDMI 2.1 and can easily run games in 120HZ 1440p from what I've seen.
Click to expand...

You can do 120hz 1440p actually over HDMI 2.0. It's 4k 120Hz that is the trick.
 
R-T-B said:
You can do 120hz 1440p actually over HDMI 2.0. It's 4k 120Hz that is the trick.
Click to expand...

Yep, true. I guess I'll prefer the high refresh rate and everything on ultra on 1440p instead of trying to do it all on 4K. Cheers for the answer though, I'll now hunt an RX 6800 XT knowing that I'll safely be able to use 40-120Hz freesync on my LG B9! :love:
 
^ Exactly, this is what you get when you don't have access to hardware and release product that's suppose to be "future proof".
 
doich said:
Yep, true. I guess I'll prefer the high refresh rate and everything on ultra on 1440p instead of trying to do it all on 4K. Cheers for the answer though, I'll now hunt an RX 6800 XT knowing that I'll safely be able to use 40-120Hz freesync on my LG B9! :love:
Click to expand...
1440p is blurry on a 4k screen...
 
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