Monitor Unrecognized Through DisplayPort, OK Through HDMI w/ R9 270X

HarlemSquirrel · 2015-01-27 15:58:54

I just upgraded from Sapphire AMD R7 260X to Sapphire R9 270X and am having issues with the DisplayPort. I get the wrong resolutions and unknown monitor only when connecting through DP, but everything works fine through HDMI. I am using an ASUS PB278Q 27" monitor at 1440p. The DP worked fine on the R7 260X. I was able to manually add my resultion using this xrandr guide but of course this does not persist through reboot, is quite annoying, and should not be necessary. Does this sound like a hardware bug to anyone? Should I be contacting Sapphire?

$ xrandr
Screen 0: minimum 320 x 200, current 2560 x 1440, maximum 16384 x 16384
DisplayPort-0 connected primary 2560x1440+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
   1024x768      60.00  
   800x600       60.32    56.25  
   848x480       60.00  
   640x480       59.94  
   2560x1440_60.00  59.96* 
HDMI-0 disconnected (normal left inverted right x axis y axis)
DVI-0 disconnected (normal left inverted right x axis y axis)
DVI-1 disconnected (normal left inverted right x axis y axis)

The EDID info seems really messed up...

$ sudo get-edid
This is read-edid version 3.0.1. Prepare for some fun.
Attempting to use i2c interface
Looks like no busses have an EDID. Sorry!
Attempting to use the classical VBE interface

	Performing real mode VBE call
	Interrupt 0x10 ax=0x4f00 bx=0x0 cx=0x0
	Function supported
	Call successful

	VBE version 300
	VBE string at 0xc0244 "AMD ATOMBIOS"

VBE/DDC service about to be called
	Report DDC capabilities

	Performing real mode VBE call
	Interrupt 0x10 ax=0x4f15 bx=0x0 cx=0x0
	Function supported
	Call successful

	Monitor and video card combination does not support DDC1 transfers
	Monitor and video card combination supports DDC2 transfers
	0 seconds per 128 byte EDID block transfer
	Screen is not blanked during DDC transfer

Reading next EDID block

VBE/DDC service about to be called
	Read EDID

	Performing real mode VBE call
	Interrupt 0x10 ax=0x4f15 bx=0x1 cx=0x0
	Function supported
	Call successful

i'e
           <"x:TO&
PT@qOV^)P0 5UP!E2LMTF003173
Lc@8<ASUS PB278
EDID claims 1 more blocks left


*********** Something special has happened!
This happens a lot with TV's, and other devices
with extension blocks. If you have a TV, don't bother.
Otherwise, please contact the author, Matthew Kern
E-mail: pyrophobicman@gmail.com
Please include full output from this program (especially that to stderr)



Reading next EDID block

VBE/DDC service about to be called
	Read EDID

	Performing real mode VBE call
	Interrupt 0x10 ax=0x4f15 bx=0x1 cx=0x0
	Function supported
	Call successful

  i'e
               <"x:TO&
PT@qOV^)P0 5UP!E2LMTF003173
Lc@8<ASUS PB278
EDID claims 1 more blocks left
EDID blocks left is wrong.
Your EDID is probably invalid.
  Looks like VBE was successful. Have a good day.

HarlemSquirrel · 2015-03-05 23:42:31

This is still a problem with the 3.19 kernel in testing as of today.

Arch Linux

#1 2015-01-27 15:58:54

Monitor Unrecognized Through DisplayPort, OK Through HDMI w/ R9 270X

#2 2015-03-05 23:42:31

Re: Monitor Unrecognized Through DisplayPort, OK Through HDMI w/ R9 270X

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