我有一台配备“i7-8665U”的联想 ThinkPad T490，它通过 USB-C/Thunderbolt 端口支持 4k@60hz，具体如下：
- 英特尔文档：https://ark.intel.com/content/www/pl/pl/ark/products/193563/intel-core-i7-8665u-processor-8m-cache-up-to-4-80-ghz.html
- 联想手册：https://download.lenovo.com/pccbbs/mobiles_pdf/t490_t590_p43s_p53s_ug_v2_en.pdf?linkTrack=PSP:ProductInfo:UserGuide
它通过 usb-c 至 hdmi2.0 电缆连接到 acer vg280k。
所有这些都与 Ubuntu 18.04.4 LTS 有关。
xrandr 不显示 4k@60hz 模式：
...
DP-1 connected primary 3840x2160+0+0 (0xa4) normal (normal left inverted right x axis y axis) 621mm x 341mm
Identifier: 0x43
Timestamp: 1074432
Subpixel: unknown
Gamma: 1.0:1.0:1.0
Brightness: 1.0
Clones: HDMI-1
CRTC: 0
CRTCs: 0 1 2
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
_MUTTER_PRESENTATION_OUTPUT: 0
EDID:
00ffffffffffff0004724707a7f65001
0f1e0103803e22782aad65ad50459f25
0e5054bfef80714f8140818081c08100
9500b300d1c04dd000a0f0703e803030
35006d552100001a565e00a0a0a02950
302035006d552100001e000000fd0028
3c1ea03c000a202020202020000000fc
0056473238304b0a202020202020011e
02034df151010304121305141f100706
025d5e5f606123090707830100006d03
0c001000383c20006001020367d85dc4
01788003681a00000101283ce6e305e3
01e40f008001e6060701606045023a80
1871382d40582c45006d552100001e8c
0ad08a20e02d10103e96006d55210000
180000000000000000000000000000a6
Content Protection: Undesired
supported: Undesired, Desired, Enabled
max bpc: 12
range: (6, 12)
Broadcast RGB: Automatic
supported: Automatic, Full, Limited 16:235
audio: auto
supported: force-dvi, off, auto, on
link-status: Good
supported: Good, Bad
CONNECTOR_ID: 92
supported: 92
non-desktop: 0
range: (0, 1)
3840x2160 (0xa4) 297.000MHz +HSync +VSync *current
h: width 3840 start 4016 end 4104 total 4400 skew 0 clock 67.50KHz
v: height 2160 start 2168 end 2178 total 2250 clock 30.00Hz
3840x2160 (0xa5) 297.000MHz +HSync +VSync
h: width 3840 start 4896 end 4984 total 5280 skew 0 clock 56.25KHz
v: height 2160 start 2168 end 2178 total 2250 clock 25.00Hz
3840x2160 (0xa6) 297.000MHz +HSync +VSync
h: width 3840 start 5116 end 5204 total 5500 skew 0 clock 54.00KHz
v: height 2160 start 2168 end 2178 total 2250 clock 24.00Hz
3840x2160 (0xa7) 296.703MHz +HSync +VSync
h: width 3840 start 4016 end 4104 total 4400 skew 0 clock 67.43KHz
v: height 2160 start 2168 end 2178 total 2250 clock 29.97Hz
3840x2160 (0xa8) 296.703MHz +HSync +VSync
h: width 3840 start 5116 end 5204 total 5500 skew 0 clock 53.95KHz
v: height 2160 start 2168 end 2178 total 2250 clock 23.98Hz
2560x1440 (0xa9) 241.500MHz +HSync +VSync
h: width 2560 start 2608 end 2640 total 2720 skew 0 clock 88.79KHz
v: height 1440 start 1443 end 1448 total 1481 clock 59.95Hz
1920x1080 (0xaa) 148.500MHz +HSync +VSync
h: width 1920 start 2008 end 2052 total 2200 skew 0 clock 67.50KHz
v: height 1080 start 1084 end 1089 total 1125 clock 60.00Hz
1920x1080 (0xab) 148.500MHz +HSync +VSync
h: width 1920 start 2448 end 2492 total 2640 skew 0 clock 56.25KHz
v: height 1080 start 1084 end 1089 total 1125 clock 50.00Hz
1920x1080 (0xac) 148.352MHz +HSync +VSync
h: width 1920 start 2008 end 2052 total 2200 skew 0 clock 67.43KHz
v: height 1080 start 1084 end 1089 total 1125 clock 59.94Hz
1920x1080i (0xad) 74.250MHz +HSync +VSync Interlace
h: width 1920 start 2008 end 2052 total 2200 skew 0 clock 33.75KHz
v: height 1080 start 1084 end 1094 total 1125 clock 60.00Hz
1920x1080i (0xae) 74.250MHz +HSync +VSync Interlace
h: width 1920 start 2448 end 2492 total 2640 skew 0 clock 28.12KHz
v: height 1080 start 1084 end 1094 total 1125 clock 50.00Hz
1920x1080i (0xaf) 74.176MHz +HSync +VSync Interlace
h: width 1920 start 2008 end 2052 total 2200 skew 0 clock 33.72KHz
v: height 1080 start 1084 end 1094 total 1125 clock 59.94Hz
1680x1050 (0x4e) 119.000MHz +HSync -VSync
h: width 1680 start 1728 end 1760 total 1840 skew 0 clock 64.67KHz
v: height 1050 start 1053 end 1059 total 1080 clock 59.88Hz
1280x1024 (0xb0) 135.000MHz +HSync +VSync
h: width 1280 start 1296 end 1440 total 1688 skew 0 clock 79.98KHz
v: height 1024 start 1025 end 1028 total 1066 clock 75.02Hz
1280x1024 (0x55) 108.000MHz +HSync +VSync
h: width 1280 start 1328 end 1440 total 1688 skew 0 clock 63.98KHz
v: height 1024 start 1025 end 1028 total 1066 clock 60.02Hz
1440x900 (0xb1) 88.750MHz +HSync -VSync
h: width 1440 start 1488 end 1520 total 1600 skew 0 clock 55.47KHz
v: height 900 start 903 end 909 total 926 clock 59.90Hz
1280x960 (0x59) 108.000MHz +HSync +VSync
h: width 1280 start 1376 end 1488 total 1800 skew 0 clock 60.00KHz
v: height 960 start 961 end 964 total 1000 clock 60.00Hz
1280x800 (0x63) 71.000MHz +HSync -VSync
h: width 1280 start 1328 end 1360 total 1440 skew 0 clock 49.31KHz
v: height 800 start 803 end 809 total 823 clock 59.91Hz
1152x864 (0xb2) 108.000MHz +HSync +VSync
h: width 1152 start 1216 end 1344 total 1600 skew 0 clock 67.50KHz
v: height 864 start 865 end 868 total 900 clock 75.00Hz
1280x720 (0xb3) 74.250MHz +HSync +VSync
h: width 1280 start 1390 end 1430 total 1650 skew 0 clock 45.00KHz
v: height 720 start 725 end 730 total 750 clock 60.00Hz
1280x720 (0xb4) 74.250MHz +HSync +VSync
h: width 1280 start 1720 end 1760 total 1980 skew 0 clock 37.50KHz
v: height 720 start 725 end 730 total 750 clock 50.00Hz
1280x720 (0xb5) 74.176MHz +HSync +VSync
h: width 1280 start 1390 end 1430 total 1650 skew 0 clock 44.96KHz
v: height 720 start 725 end 730 total 750 clock 59.94Hz
1024x768 (0xb6) 78.750MHz +HSync +VSync
h: width 1024 start 1040 end 1136 total 1312 skew 0 clock 60.02KHz
v: height 768 start 769 end 772 total 800 clock 75.03Hz
1024x768 (0xb7) 75.000MHz -HSync -VSync
h: width 1024 start 1048 end 1184 total 1328 skew 0 clock 56.48KHz
v: height 768 start 771 end 777 total 806 clock 70.07Hz
1024x768 (0x6a) 65.000MHz -HSync -VSync
h: width 1024 start 1048 end 1184 total 1344 skew 0 clock 48.36KHz
v: height 768 start 771 end 777 total 806 clock 60.00Hz
832x624 (0xb8) 57.284MHz -HSync -VSync
h: width 832 start 864 end 928 total 1152 skew 0 clock 49.73KHz
v: height 624 start 625 end 628 total 667 clock 74.55Hz
800x600 (0xb9) 50.000MHz +HSync +VSync
h: width 800 start 856 end 976 total 1040 skew 0 clock 48.08KHz
v: height 600 start 637 end 643 total 666 clock 72.19Hz
800x600 (0xba) 49.500MHz +HSync +VSync
h: width 800 start 816 end 896 total 1056 skew 0 clock 46.88KHz
v: height 600 start 601 end 604 total 625 clock 75.00Hz
800x600 (0x79) 40.000MHz +HSync +VSync
h: width 800 start 840 end 968 total 1056 skew 0 clock 37.88KHz
v: height 600 start 601 end 605 total 628 clock 60.32Hz
800x600 (0x7a) 36.000MHz +HSync +VSync
h: width 800 start 824 end 896 total 1024 skew 0 clock 35.16KHz
v: height 600 start 601 end 603 total 625 clock 56.25Hz
720x576 (0xbb) 27.000MHz -HSync -VSync
h: width 720 start 732 end 796 total 864 skew 0 clock 31.25KHz
v: height 576 start 581 end 586 total 625 clock 50.00Hz
720x480 (0xbc) 27.027MHz -HSync -VSync
h: width 720 start 736 end 798 total 858 skew 0 clock 31.50KHz
v: height 480 start 489 end 495 total 525 clock 60.00Hz
720x480 (0xbd) 27.000MHz -HSync -VSync
h: width 720 start 736 end 798 total 858 skew 0 clock 31.47KHz
v: height 480 start 489 end 495 total 525 clock 59.94Hz
640x480 (0xbe) 31.500MHz -HSync -VSync
h: width 640 start 656 end 720 total 840 skew 0 clock 37.50KHz
v: height 480 start 481 end 484 total 500 clock 75.00Hz
640x480 (0xbf) 31.500MHz -HSync -VSync
h: width 640 start 664 end 704 total 832 skew 0 clock 37.86KHz
v: height 480 start 489 end 492 total 520 clock 72.81Hz
640x480 (0xc0) 30.240MHz -HSync -VSync
h: width 640 start 704 end 768 total 864 skew 0 clock 35.00KHz
v: height 480 start 483 end 486 total 525 clock 66.67Hz
640x480 (0xc1) 25.200MHz -HSync -VSync
h: width 640 start 656 end 752 total 800 skew 0 clock 31.50KHz
v: height 480 start 490 end 492 total 525 clock 60.00Hz
640x480 (0x88) 25.175MHz -HSync -VSync
h: width 640 start 656 end 752 total 800 skew 0 clock 31.47KHz
v: height 480 start 490 end 492 total 525 clock 59.94Hz
720x400 (0xc2) 28.320MHz -HSync +VSync
h: width 720 start 738 end 846 total 900 skew 0 clock 31.47KHz
v: height 400 start 412 end 414 total 449 clock 70.08Hz
HDMI-1 disconnected (normal left inverted right x axis y axis)
Identifier: 0x44
Timestamp: 1074432
Subpixel: unknown
Clones: DP-1
CRTCs: 0 1 2
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
Content Protection: Undesired
supported: Undesired, Desired, Enabled
max bpc: 12
range: (8, 12)
content type: No Data
supported: No Data, Graphics, Photo, Cinema, Game
Colorspace: Default
supported: Default, SMPTE_170M_YCC, BT709_YCC, XVYCC_601, XVYCC_709, SYCC_601, opYCC_601, opRGB, BT2020_CYCC, BT2020_RGB, BT2020_YCC, DCI-P3_RGB_D65, DCI-P3_RGB_Theater
aspect ratio: Automatic
supported: Automatic, 4:3, 16:9
Broadcast RGB: Automatic
supported: Automatic, Full, Limited 16:235
audio: auto
supported: force-dvi, off, auto, on
link-status: Good
supported: Good, Bad
CONNECTOR_ID: 99
supported: 99
non-desktop: 0
range: (0, 1)
DP-2 disconnected (normal left inverted right x axis y axis)
Identifier: 0x45
Timestamp: 1074432
Subpixel: unknown
Clones: HDMI-2
CRTCs: 0 1 2
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
Content Protection: Undesired
supported: Undesired, Desired, Enabled
max bpc: 12
range: (6, 12)
Broadcast RGB: Automatic
supported: Automatic, Full, Limited 16:235
audio: auto
supported: force-dvi, off, auto, on
link-status: Good
supported: Good, Bad
CONNECTOR_ID: 105
supported: 105
non-desktop: 0
range: (0, 1)
HDMI-2 disconnected (normal left inverted right x axis y axis)
Identifier: 0x46
Timestamp: 1074432
Subpixel: unknown
Clones: DP-2
CRTCs: 0 1 2
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
filter:
Content Protection: Undesired
supported: Undesired, Desired, Enabled
max bpc: 12
range: (8, 12)
content type: No Data
supported: No Data, Graphics, Photo, Cinema, Game
Colorspace: Default
supported: Default, SMPTE_170M_YCC, BT709_YCC, XVYCC_601, XVYCC_709, SYCC_601, opYCC_601, opRGB, BT2020_CYCC, BT2020_RGB, BT2020_YCC, DCI-P3_RGB_D65, DCI-P3_RGB_Theater
aspect ratio: Automatic
supported: Automatic, 4:3, 16:9
Broadcast RGB: Automatic
supported: Automatic, Full, Limited 16:235
audio: auto
supported: force-dvi, off, auto, on
link-status: Good
supported: Good, Bad
CONNECTOR_ID: 110
supported: 110
non-desktop: 0
range: (0, 1)
当我添加通过（受限或不受限制）生成的手动模式时，cvt出现此错误：
$ xrandr --output DP-1 --mode "3840x2160R" --verbose
crtc 0: 3840x2160R 59.97 +0+0 "DP-1"
xrandr: Configure crtc 0 failed
crtc 0: disable
crtc 1: disable
crtc 2: disable
screen 0: revert
crtc 0: revert
crtc 1: revert
crtc 2: revert
答案1
最终的解决方案是购买明确支持 4k@60hz 的电缆
答案2
我的笔记本电脑 HP ProBook 450 G7 也遇到了同样的问题。我只能获得 4K@30Hz。经过研究，我购买了一根 USB-C 转 HDMI 电缆，解决了这个问题。奇怪的是，HDMI 端口限制为 30Hz，但 USB-C 端口最高可达 60Hz。希望这对某些人有帮助
答案3
以防万一有人在谷歌上搜索这个问题并发现这一点：我遇到了同样的问题，对我来说，解决办法是直接使用 HDMI。我有一个 DP 转 HDMI 的适配器，同样的设置在 Windows 上通过该适配器以 4k 60Hz 运行，但在我安装 Ubuntu 后，它只能达到 30Hz。在我移除适配器并将 HDMI 电缆直接插入 GPU 后，我重新启动了，它默认选择了这个配置文件：
HDMI-0 连接 3840x2160+0+0（正常左反转右 x 轴 y 轴） 1872mm x 1053mm 3840x2160 60.00*+ 59.94 50.00 29.97 25.00 23.98
我使用的是适配器，因为我有两个带 HDMI 的显示器，而 GPU 只有一个 HDMI 输出和 3 个 DP 端口。另一个显示器只有 1080p，所以通过该适配器可以正常工作。
答案4
我遇到了类似的问题，用 DisplayPort 电缆替换 HDMI 电缆解决了这个问题。我的 USB-C 基座和屏幕有两个可用端口。使用 HDMI，我只能选择 4k@30Hz。选择 60Hz 会变暗并切换回来。使用 DisplayPort 电缆后，一切都运行正常。