Custom Resolution Utility (CRU)

[dinova1]

Thanks that worked!

(08-21-2017 01:06 AM)ToastyX Wrote:  That looks like a partially corrupt or misprogrammed EDID. It's possible only the product ID is corrupt, which wouldn't affect any functionality. You can change the product ID to any 3-letter + 4-digit hex value you want. I think the default for that monitor is HKC0000. That should let you save.

[aliquis]

Hello, i did what you suggested and used the reset all program after creating a backup. Indeed now the heavy flickering during freesync is back!

Here are CRU screenshots: [Image: http://imgur.com/a/wX2Xb]

in the screenshot you see the out of the box settings, i changed nothing( the screen now flickers during freesync) .

Now i think i can be more precise about what i did modify in the first place before i used reset all and what i thought and maybe after all fixed the flicker, i modified a custom resolution (in the bottom part of the screenshot) to 100hz (With appropriate pixel clock and h rate), note: i noticed that the other resolutions do indeed have a slightly lower v total of 1481 instead of the 1510 used in the single 99,981hz resolution (again, i changed nothing this time, these are the out of the box values and the screen is flickering severly)

edit: I just noticed that a tech youtube channel has released a video about this exact freesync flicker issue on the samsung cf791, https://youtu.be/iZ7N4GLoiBA
)

[ToastyX]

(08-21-2017 07:13 AM)aliquis Wrote:  Hello, i did what you suggested and used the reset all program after creating a backup. Indeed now the heavy flickering during freesync is back!

Here are CRU screenshots: [Image: http://imgur.com/a/wX2Xb]

in the screenshot you see the out of the box settings, i changed nothing( the screen now flickers during freesync) .

Now i think i can be more precise about what i did modify in the first place before i used reset all and what i thought and maybe after all fixed the flicker, i modified a custom resolution (in the bottom part of the screenshot) to 100hz (With appropriate pixel clock and h rate), note: i noticed that the other resolutions do indeed have a slightly lower v total of 1481 instead of the 1510 used in the single 99,981hz resolution (again, i changed nothing this time, these are the out of the box values and the screen is flickering severly)

I don't see anything strange about the timing parameters. Those are just the CVT-RB standard values for 3840x1440 @ 60 Hz (1481) and 100 Hz (1510). "LCD standard" returns the same values. "LCD native" always returns the 60 Hz timing parameters, so you can use that instead of changing the vertical total manually. I don't see why that would make a difference though. If using the 60 Hz timing parameters works around the problem, then either there's a design flaw with the monitor, or there's an issue with the way FreeSync is implemented by the GPU.

[aliquis]

Although i purchased this monitor about 8 months ago, it seems AMD is at least aware of the problem. They released a new driver today that has the following fix in its patchnotes:

Quote:FreeSync brightness or flickering issues have been resolved on a small amount of Samsung FreeSync enabled displays that may have been experiencing issues.

After installing the new driver, the issue seems to be resolved (at least i hope so )

Thank you for the help/ responses

[ToastyX]

(08-21-2017 10:51 PM)aliquis Wrote:  Although i purchased this monitor about 8 months ago, it seems AMD is at least aware of the problem. They released a new driver today that has the following fix in its patchnotes:

Quote:FreeSync brightness or flickering issues have been resolved on a small amount of Samsung FreeSync enabled displays that may have been experiencing issues.

After installing the new driver, the issue seems to be resolved (at least i hope so )

Thank you for the help/ responses

That's interesting. I wonder if they actually fixed something or if they just implemented a workaround. It seems odd that a driver issue would specifically affect certain Samsung monitors.

[okwei]

Can setting be persisted? each time my computer restarts or sleep/wake, the monitor will lose the custom resolution it was set to. I had to run restart.exe every time.. Am I missing something or this is expected?

[ToastyX]

(08-26-2017 02:14 PM)okwei Wrote:  Can setting be persisted? each time my computer restarts or sleep/wake, the monitor will lose the custom resolution it was set to. I had to run restart.exe every time.. Am I missing something or this is expected?

CRU simply saves an EDID override. The graphics driver implements the resolutions. The settings are supposed to persist. If they don't, that's a graphics driver bug. Running restart.exe simply restarts the graphics driver, which causes it to reload the settings that are already saved. Any issue that goes away after running restart.exe is a graphics driver bug. What GPU do you have?

[okwei]

(08-26-2017 04:32 PM)ToastyX Wrote:  

(08-26-2017 02:14 PM)okwei Wrote:  Can setting be persisted? each time my computer restarts or sleep/wake, the monitor will lose the custom resolution it was set to. I had to run restart.exe every time.. Am I missing something or this is expected?

CRU simply saves an EDID override. The graphics driver implements the resolutions. The settings are supposed to persist. If they don't, that's a graphics driver bug. Running restart.exe simply restarts the graphics driver, which causes it to reload the settings that are already saved. Any issue that goes away after running restart.exe is a graphics driver bug. What GPU do you have?

I have the intel HD 530. I try to force a 3840x1600 30HZ resolution since that's what the HDMI1.4 port support on my laptop. Resolution works fine except I had to either do the restart, or re-plug the HDMI cable.. Is this really a graphic card driver bug?

[ToastyX]

(08-27-2017 02:15 AM)okwei Wrote:  I have the intel HD 530. I try to force a 3840x1600 30HZ resolution since that's what the HDMI1.4 port support on my laptop. Resolution works fine except I had to either do the restart, or re-plug the HDMI cable.. Is this really a graphic card driver bug?

Yes, but there might be a workaround. What monitor is this? Is there a "Default extension block" in the extension block list?

[okwei]

(08-27-2017 03:58 AM)ToastyX Wrote:  

(08-27-2017 02:15 AM)okwei Wrote:  I have the intel HD 530. I try to force a 3840x1600 30HZ resolution since that's what the HDMI1.4 port support on my laptop. Resolution works fine except I had to either do the restart, or re-plug the HDMI cable.. Is this really a graphic card driver bug?

Yes, but there might be a workaround. What monitor is this? Is there a "Default extension block" in the extension block list?

it's the new dell 38" U3818dw. Extension block? I got the folowing