i'm trying to connect an external monitor to my Lenovo T420 using the DisplayPort but it's not working. If i connect it via VGA it works fine, but the image on the monitor is lacking sharpness and it's flickering (the cause of that I discovered to be some interference in the VGA output). So, I want to connect my external monitor using DisplayPort, but when i do so, i get no image on it. And when i run the xrandr command, I don't see any display port:
$ xrandr Screen 0: minimum 320 x 200, current 3520 x 1200, maximum 32767 x 32767 LVDS1 connected 1600x900+0+300 (normal left inverted right x axis y axis) 309mm x 174mm 1600x900 60.0*+ 40.0 1440x900 59.9 1360x768 59.8 60.0 1152x864 60.0 1024x768 60.0 800x600 60.3 56.2 640x480 59.9 VGA1 connected 1920x1200+1600+0 (normal left inverted right x axis y axis) 518mm x 324mm 1920x1200 60.0*+ 1920x1080 59.9 1600x1200 60.0 1680x1050 60.0 1280x1024 75.0 72.0 60.0 1440x900 75.0 59.9 1024x768 75.1 70.1 60.0 800x600 72.2 75.0 60.3 640x480 72.8 75.0 66.0 60.0 720x400 70.1
When running lspci -v i can see both my graphic cards:
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) (prog-if 00 [VGA controller]) Subsystem: Lenovo Device 21d0 Flags: bus master, fast devsel, latency 0, IRQ 46 Memory at f1400000 (64-bit, non-prefetchable) [size=4M] Memory at e0000000 (64-bit, prefetchable) [size=256M] I/O ports at 6000 [size=64] Expansion ROM at <unassigned> [disabled] Capabilities: <access denied> Kernel driver in use: i915
01:00.0 VGA compatible controller: NVIDIA Corporation GF119M [Quadro NVS 4200M] (rev a1) (prog-if 00 [VGA controller]) Subsystem: Lenovo Device 21d0 Flags: fast devsel, IRQ 11 Memory at f0000000 (32-bit, non-prefetchable) [disabled] [size=16M] Memory at c0000000 (64-bit, prefetchable) [disabled] [size=256M] Memory at d0000000 (64-bit, prefetchable) [disabled] [size=32M] I/O ports at 5000 [disabled] [size=128] Expansion ROM at f1000000 [disabled] [size=512K] Capabilities: <access denied>
In Bios my settings are "Discrete Graphics" and OS detection Disabled. Any idea what i could do to make the display port work?
I'm running Ubuntu 13.04.