I'm not sure if this is a hardware/software limitation or a bug, but I can't seem to enable LVDS, VGA and HDMI outputs at the same time. Enabling any two works fine (have to disable the 3rd). Fedora 17 i686 xorg-x11-drv-intel-devel.i686 2.20.10-2.fc17 SNA is enabled 00:02.0 VGA compatible controller [0300]: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0116] (rev 09) (prog-if 00 [VGA controller]) Subsystem: Lenovo Device [17aa:3975] 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 Interrupt: pin A routed to IRQ 41 Region 0: Memory at e8400000 (64-bit, non-prefetchable) [size=4M] Region 2: Memory at d0000000 (64-bit, prefetchable) [size=256M] Region 4: I/O ports at 1800 [size=64] Expansion ROM at <unassigned> [disabled] Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit- Address: fee0f00c Data: 41a1 Capabilities: [d0] Power Management version 2 Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-) Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME- Capabilities: [a4] PCI Advanced Features AFCap: TP+ FLR+ AFCtrl: FLR- AFStatus: TP- Kernel driver in use: i915
Here's what I get when trying to enable 3rd output with xrandr (VGA1 and HDMI1 are already running): $ xrandr --output LVDS1 --auto xrandr: cannot find crtc for output LVDS1 This also happens if VGA1 and HDMI1 are disconnected -- but that's probably a bug of xrandr Running "xrandr --output VGA1 --off" and/or "xrandr --output HDMI1 --off" before the command above fixes the issue in both cases
Note that ivb has 3 output pipes, but only two plls. Which means that you need to select modes with the same dotclock on at least two outputs (VGA and HMDI here, since LVDS runs at its fixed mode always). It's a hw limitation. Furthermore you need to run at latest drm-intel-fixes from http://cgit.freedesktop.org/~danvet/drm-intel to avoid hitting known bugs with ivb 3 pipe. So please attach xrandr --verbose and retest with the above kernel so we know whether this is wontfix, already fixed or a new bug.
SandyBridge (2nd Generation Core Processor) only supports two active outputs.
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.