我有一台 DELL Inspiron 14 笔记本，Ubuntu 19.04，配有 AMD radeon 显卡。我正在尝试让 LG ULtrawide 显示器与我的笔记本电脑配合使用。
已经在 LG 电视上测试了我的笔记本电脑，运行完美。此外，LG 显示器可以与我拥有的一台 PC 以及我去检查是否运行正常的商店的一台 PC 配合使用。我不明白为什么这台显示器和我的笔记本电脑不能一起工作，即使它们都可以正常工作。
即使连接了 HDMI 线，显示设置和 xrandr 仍然会像这样报告断开连接。
HDMI-1 disconnected (normal left inverted right x axis y axis) 0mm x 0mm
另外，当我使用 xrand 强制显示器的正确分辨率（newmode、addmode、2560 x 1080_60）时，它开始部分工作，仅渲染屏幕的 1/4（不完全是）。（鼠标在整个屏幕上工作）
xrandr --output HDMI-1 --mode "2560x1080_60.00"
将其设置为比例时，屏幕变黑，只有鼠标可以在显示器上使用。如果我将任何打开的窗口拖到此显示器，它会出现延迟和重复的情况。
xrandr --output HDMI-1 --scale 1x1 --right-of eDP-1 --mode "2560x1080_60.00"
发生了一件奇怪的事情，即鼠标光标在整个屏幕上都可以工作，即使显示器只显示部分内容
我现在使用的是 ubuntu 19.04，但也在 18.04 中测试过，问题完全一样。目前，我正在下载 ubuntu 14.04 以使用旧版本的驱动程序/内核对其进行测试。
xrand：
Screen 0: minimum 320 x 200, current 2560 x 1080, maximum 16384 x 16384
eDP-1 connected 1366x768+0+0 (normal left inverted right x axis y axis) 309mm x 173mm
1366x768 60.00*+ 48.00
1360x768 59.80 59.96
1280x720 60.00 59.99 59.86 59.74
1024x768 60.04 60.00
960x720 60.00
928x696 60.05
896x672 60.01
1024x576 59.95 59.96 59.90 59.82
960x600 59.93 60.00
960x540 59.96 59.99 59.63 59.82
800x600 60.00 60.32 56.25
840x525 60.01 59.88
864x486 59.92 59.57
800x512 60.17
700x525 59.98
800x450 59.95 59.82
640x512 60.02
720x450 59.89
700x450 59.96 59.88
640x480 60.00 59.94
720x405 59.51 58.99
684x384 59.88 59.85
680x384 59.80 59.96
640x400 59.88 59.98
576x432 60.06
640x360 59.86 59.83 59.84 59.32
512x384 60.00
512x288 60.00 59.92
480x270 59.63 59.82
400x300 60.32 56.34
432x243 59.92 59.57
320x240 60.05
360x202 59.51 59.13
320x180 59.84 59.32
HDMI-1 disconnected primary 2560x1080+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
2560x1080_60.00 59.98*
lspci-vv
04:00.0 Display controller: Advanced Micro Devices, Inc. [AMD/ATI] Topaz XT [Radeon R7 M260/M265 / M340/M360 / M440/M445]
Subsystem: Dell Radeon R7 M260/M265
Physical Slot: 4
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 54
Region 0: Memory at b0000000 (64-bit, prefetchable) [size=256M]
Region 2: Memory at c0000000 (64-bit, prefetchable) [size=2M]
Region 4: I/O ports at 3000 [size=256]
Region 5: Memory at c2000000 (32-bit, non-prefetchable) [size=256K]
Expansion ROM at c2040000 [disabled] [size=128K]
Capabilities: [48] Vendor Specific Information: Len=08 <?>
Capabilities: [50] Power Management version 3
Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
Capabilities: [58] Express (v2) Legacy Endpoint, MSI 00
DevCap: MaxPayload 256 bytes, PhantFunc 0, Latency L0s <4us, L1 unlimited
ExtTag+ AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq-
RlxdOrd+ ExtTag+ PhantFunc- AuxPwr- NoSnoop+
MaxPayload 128 bytes, MaxReadReq 512 bytes
DevSta: CorrErr+ NonFatalErr- FatalErr- UnsupReq+ AuxPwr- TransPend-
LnkCap: Port #0, Speed 5GT/s, Width x8, ASPM L0s L1, Exit Latency L0s <64ns, L1 <1us
ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp+
LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk+
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 5GT/s (ok), Width x4 (downgraded)
TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
DevCap2: Completion Timeout: Not Supported, TimeoutDis-, LTR-, OBFF Not Supported
AtomicOpsCap: 32bit- 64bit- 128bitCAS-
DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled
AtomicOpsCtl: ReqEn-
LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
Compliance De-emphasis: -6dB
LnkSta2: Current De-emphasis Level: -6dB, EqualizationComplete-, EqualizationPhase1-
EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
Capabilities: [a0] MSI: Enable+ Count=1/1 Maskable- 64bit+
Address: 00000000fee00418 Data: 0000
Capabilities: [100 v1] Vendor Specific Information: ID=0001 Rev=1 Len=010 <?>
Capabilities: [150 v2] Advanced Error Reporting
UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout- AdvNonFatalErr-
CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout- AdvNonFatalErr+
AERCap: First Error Pointer: 00, ECRCGenCap+ ECRCGenEn- ECRCChkCap+ ECRCChkEn-
MultHdrRecCap- MultHdrRecEn- TLPPfxPres- HdrLogCap-
HeaderLog: 00000000 00000000 00000000 00000000
Capabilities: [270 v1] Secondary PCI Express <?>
Capabilities: [2b0 v1] Address Translation Service (ATS)
ATSCap: Invalidate Queue Depth: 00
ATSCtl: Enable-, Smallest Translation Unit: 00
Capabilities: [2c0 v1] Page Request Interface (PRI)
PRICtl: Enable- Reset-
PRISta: RF- UPRGI- Stopped+
Page Request Capacity: 00000020, Page Request Allocation: 00000000
Capabilities: [2d0 v1] Process Address Space ID (PASID)
PASIDCap: Exec+ Priv+, Max PASID Width: 10
PASIDCtl: Enable- Exec- Priv-
Kernel driver in use: amdgpu
Kernel modules: amdgpu
xrandr --listproviders
Providers: number : 2
Provider 0: id: 0x64 cap: 0x9, Source Output, Sink Offload crtcs: 3 outputs: 2 associated providers: 1 name:modesetting
Provider 1: id: 0x3f cap: 0x4, Source Offload crtcs: 0 outputs: 0 associated providers: 1 name:AMD Radeon R7 M260 @ pci:0000:04:00.0
dmesg 也显示奇怪的东西：
[ 33.384861] amdgpu: [powerplay] VI should always have 2 performance levels
[ 33.417539] amdgpu 0000:04:00.0: GPU pci config reset
[ 35.086922] [drm] PCIE GART of 256M enabled (table at 0x000000F400000000).
[ 35.093000] amdgpu: [powerplay] can't get the mac of 5
[ 35.094140] amdgpu: [powerplay] VBIOS did not find boot engine clock value in dependency table. Using Memory DPM level 0!
[ 39.516060] i915 0000:00:02.0: HDMI-A-1: EDID is invalid:
[ 39.516065] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 39.516066] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 39.516068] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 39.516069] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 39.516070] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 39.516072] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 39.516073] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 39.516074] [00] ZERO 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 41.291476] amdgpu: [powerplay] VI should always have 2 performance levels
[ 41.330509] amdgpu 0000:04:00.0: GPU pci config reset