Monitor Tests Forum

Hi here is what I have under ubuntu, the edid is fine :


Any idea ?
So the problem is in the bios ? something tell windows and the intel drivers to choose 52hz ?
Before the bios update windows let me choose the refresh rate, and I was at 60Hz.
I think I need and EDID Override INF to test, can someone know how to do it ?
With the values I have provided.

EDIT : I made this inf in Monitor asset is this an EDID Override ?
https://ctxt.io/2/AADAn2QFFw

I have questions regarding effect of changing Vertical Blanking to my monitor.

I have the "memclock maxed out at 144 Hz" issue (not downclocking at idle).

I made a backup first of my monitor's original config. So at the CRU 1st page, it says low vertical blanking causes this maxed out memclock thing. So what I did was to change only the Vertical Blanking from 50 to 100. And it worked! Pixel clock is less than max of 600 Mhz (HDMI 2) so I feel it is fine. But..

1. Can anyone explain how this works?
2. I noticed that increasing the VB also increased back porch V and total V lines. Will this affect my monitor in any way? Like its parts, its health, gaming experience (flickering, etc)?
3. Freesync is now disabled in AMD Software. Can this be fixed?



ViewSonic VX2758-2KP-MHD
1440p @ 144 Hz using HMDI 2
60, 120, 144 Hz are the default refresh rates of this monitor

EDIT: I only doubled the VB but LOL lots of flickering in games. It also broke Freesync. I had to delete - reboot to bring my monitor back to default.

Hello guys, I fixed my screen refresh rate, and it was the bios !!!!

More specifically in the CSM module.
I had to boot the GPU in "Legacy mode" to get rid of the VideoBios messing the settings under windows. Booting with the GPU in "UEFI mode" = 52hz.
The weird thing is that if I disable CSM completely I am locked again at 52hz in Win10.

Maybe even an EDID override would have not worked in UEFI mode. GPU probably had a baked in EDID or setting in UEFI mode ?

To fix the screen flicker they probably had to modify the VideoBios and they messed up the uefi mode ?
It seems Linux don't care about CSM settings, and use legacy mode for video probably ??? that is why it was not affected ?

Now my screen is recognized as MEI96A2, and the refresh rate is 60.
I can set it at 50hz in CRU now !

Thank you very much.
I left the solution here in hope to help anyone with the same problem.

(08-25-2020 03:44 PM)vigan1 Wrote: [ -> ]I think I need and EDID Override INF to test, can someone know how to do it ?
With the values I have provided.

EDIT : I made this inf in Monitor asset is this an EDID Override ?
https://ctxt.io/2/AADAn2QFFw

CRU already creates EDID overrides, so it probably wouldn't have mattered. Glad you found a solution.

(08-25-2020 04:38 PM)bampi Wrote: [ -> ]1. Can anyone explain how this works?
2. I noticed that increasing the VB also increased back porch V and total V lines. Will this affect my monitor in any way? Like its parts, its health, gaming experience (flickering, etc)?
3. Freesync is now disabled in AMD Software. Can this be fixed?

1. Increasing the vertical blanking gives the GPU more time between screen refreshes to retrain the memory when changing clock speeds. If the vertical blanking is too low, it won't have enough time to retrain the memory without corrupting the screen contents.
2. Increasing the blanking also increases the bandwidth used, but as long as it works, there shouldn't be a problem. The monitor might not be able to display the increased blanking correctly though.
3. I don't see why that would disable FreeSync.

(08-26-2020 04:09 PM)ToastyX Wrote: [ -> ]

(08-25-2020 03:44 PM)vigan1 Wrote: [ -> ]I think I need and EDID Override INF to test, can someone know how to do it ?
With the values I have provided.

EDIT : I made this inf in Monitor asset is this an EDID Override ?
https://ctxt.io/2/AADAn2QFFw

CRU already creates EDID overrides, so it probably wouldn't have mattered. Glad you found a solution.

Thank you for your kindness.

2 days ago, the manufacturer responded me saying "Yes the latest and Final bios lock the refresh rate at 52Hz. Thank you for your support.", I am pretty sure they don't care to fix it they are one of the new Chinese manufacturer.

To get perfect 50hz and 25Hz, do I have to just let CRU use "Automatic - LCD standard" and Input 50hz ?
Or should I do it manually from the value present in the edid of my screen ?

Because If I use AUTOMATIC, the polarity is +/-, but after a fresh install of linux or windows the polarity is +/+.
EDIT : In the EDID it' also +/+ , is it really affecting the panel ?

Thank you.

(08-27-2020 10:15 AM)vigan1 Wrote: [ -> ]To get perfect 50hz and 25Hz, do I have to just let CRU use "Automatic - LCD standard" and Input 50hz ?
Or should I do it manually from the value present in the edid of my screen ?

Because If I use AUTOMATIC, the polarity is +/-, but after a fresh install of linux or windows the polarity is +/+.
EDIT : In the EDID it' also +/+ , is it really affecting the panel ?

The polarity doesn't matter. To get exactly 50 Hz, use the timing parameters you posted earlier and change the vertical total to 2065, or use "LCD standard" and then switch to "Manual" and change the vertical total to 2050. Keep in mind that just sets the logical refresh rate to exactly 50 Hz. The actual physical refresh rate might be slightly off depending on the hardware clock precision. It might be more accurate with an integer pixel clock. Setting the totals to 3200x2050 will give you exactly 50 Hz at exactly 328 MHz pixel clock.

hey - i am planing on buying this panel "AUO B156XTN08.1" for my Nitro 5 (Ryzen 2500U + RX560X)

can anyone confirm it gets to 100hz and has FreeSync?

(08-26-2020 10:44 AM)vigan1 Wrote: [ -> ]Hello guys, I fixed my screen refresh rate, and it was the bios !!!!

More specifically in the CSM module.
I had to boot the GPU in "Legacy mode" to get rid of the VideoBios messing the settings under windows. Booting with the GPU in "UEFI mode" = 52hz.
The weird thing is that if I disable CSM completely I am locked again at 52hz in Win10.

Maybe even an EDID override would have not worked in UEFI mode. GPU probably had a baked in EDID or setting in UEFI mode ?

To fix the screen flicker they probably had to modify the VideoBios and they messed up the uefi mode ?
It seems Linux don't care about CSM settings, and use legacy mode for video probably ??? that is why it was not affected ?

Now my screen is recognized as MEI96A2, and the refresh rate is 60.
I can set it at 50hz in CRU now !

Thank you very much.
I left the solution here in hope to help anyone with the same problem.

I'm currently experiencing what I think is a similar problem with my new laptop. In Linux is supports my desired resolution and refresh rate, however in windows I cannot set this resolution.

I understand how to use xrandr, and how to read my X log, but how to translate that into the CRU is still new to me so I'm going to poke around.

Should that fail, can you describe how you disabled the GPU legacy mode? Was this a setting provided in your BIOS/UEFI? This laptop has a very sparse BIOS configuration (lots of graphics, very little of actual use).

Thank you for your help!

(08-27-2020 02:44 PM)ToastyX Wrote: [ -> ]The polarity doesn't matter. To get exactly 50 Hz, use the timing parameters you posted earlier and change the vertical total to 2065, or use "LCD standard" and then switch to "Manual" and change the vertical total to 2050. Keep in mind that just sets the logical refresh rate to exactly 50 Hz. The actual physical refresh rate might be slightly off depending on the hardware clock precision. It might be more accurate with an integer pixel clock. Setting the totals to 3200x2050 will give you exactly 50 Hz at exactly 328 MHz pixel clock.

OK thank you I will try it and see ! I will post CRU screenshot I hope it will be ok.

(08-28-2020 02:46 PM)MaKneeTore Wrote: [ -> ]Should that fail, can you describe how you disabled the GPU legacy mode? Was this a setting provided in your BIOS/UEFI? This laptop has a very sparse BIOS configuration (lots of graphics, very little of actual use).

Thank you for your help!

First tell me what is the brand and model of you laptop. To see if you have the correct drivers, and try updating your bios.
If everything fail, you should find an option in the bios called :
Compatibility Support Module (CSM)
For me it was under ADVANCED > Compatibility Support Module (CSM).
Activate this option (it should be on by default I think) and you should see :

USB (Legacy or UEFI)
Video (Legacy / UEFI)
storage (Legacy / UEFI)

I simply selected "Legacy" under Video, and restarted.
All bios are different and some bios are completely locked, so it may not be here.