TX1 not support 4K resolution monitor

Hello everyone,

I want to connect the TX1 to a 4K monitor (Viewsonic VP3268-4K) with HDMI cable. However after I plugged the HDMI cable I found the monitor loop showing “no signal” and turning to completely black. But it seems that the monitor had detected the monitor but failed to display.

It works fine if I change the resolution to FHD, also my TX2 don’t have this problem.

Thank you.

Hi maplecirno,

This issue will be resolved in next release (rel-28.2). I also have temporary workaround, but cannot guarantee every monitor would work.


Hi Wayne,

I got the same problem, and your workaround patch does not work. TX1 works with my 1080p ASUS display but not with my Viewsonic VX4380-4k. It seems nVidia and Viewsonic makes no good pair.

It keeps spamming the HDMI port with on/off and spamming this message on RS232:

tegradc tegradc.1: hdmi: scdc scrambling status is reset, trying to reconfigure
tegradc tegradc.1: hdmi: scdc scrambling status is reset, trying to reconfigure
tegradc tegradc.1: hdmi: scdc scrambling status is reset, trying to reconfigure

When can we expect the next kernel rel-28.2 release ?


Hi lacid126b,

Yeah, this patch may not cover 4k monitor. This issue should have been resolved on rel-28.2DP. Could you give a quick try?

Hi Wayne,

Sure, immediately. Where can I find that rel-28.2DP ?


Oops, sorry that I didn’t notice it is a TX1 issue. rel-28.2 DP is temporary for tx2 only, but rel-28.2 official is going to be ready soon. Sorry for your inconvenience.

Meh :/
How soon ?

Hi Wayne,

I pulled the kernel from the git repo tagged as tegra-l4t-r28.2-rc , and then I built it and tried it . It didn’t work. It spammed the same message “…hdmi: scdc scrambling status is reset…” , and it got frozen eventually. The whole system I mean. So it doesn’t support TX1 obviously its for TX2 only.

Its not announced though, but I think that the R28.2 GA for TX2/TX1 will be available in months or maybe more.

And I think this is a quite serious error, because the TX1 is named as a 4k UHD video dev-board, but actually it can’t drive lot of 4k display (I got 3 kind of 4k monitor, none works).

Is there any method, any other workaround than that mentioned patch.

For example I got full EDID info of my display, here is a fragment :

Timing characteristics
Horizontal scan range… 24-160kHz
Vertical scan range… 50-75Hz
Video bandwidth… 600MHz
CVT standard… Not supported
GTF standard… Not supported
Additional descriptors… None
Preferred timing… Yes
Native/preferred timing… 3840x2160p at 60Hz (16:9)
Modeline… “3840x2160” 533.250 3840 3888 3920 4000 2160 2163 2168 2222 +hsync -vsync
Detailed timing #1… 2560x1440p at 60Hz (16:9)
Modeline… “2560x1440” 241.500 2560 2607 2639 2720 1440 1443 1448 1481 +hsync -vsync

EIA/CEA-861 Information
Revision number… 3
IT underscan… Supported
Basic audio… Supported
YCbCr 4:4:4… Supported
YCbCr 4:2:2… Supported
Native formats… 1
Detailed timing #1… 1920x2160p at 60Hz (16:9)
Modeline… “1920x2160” 277.300 1920 1968 2000 2080 2160 2163 2173 2222 +hsync +vsync
Detailed timing #2… 3840x1080p at 60Hz (16:9)
Modeline… “3840x1080” 266.500 3840 3888 3920 4000 1080 1090 1093 1111 -hsync -vsync
Detailed timing #3… 3840x2160p at 30Hz (16:9)
Modeline… “3840x2160” 262.750 3840 3888 3920 4000 2160 2163 2168 2191 +hsync -vsync

Raw data

…and more data I wish I knew what does it mean.

Is there any way to put this somehow in a .dts file to make it work ?
Please help.


Hi Wayne,

I’ve installed the new r28.2.
It works like charm with TX1.