https://bugs.freedesktop.org/show_bug.cgi?id=105534
--- Comment #7 from philipmorant@gmail.com --- There are 3 physical motherboard sockets: HDMI, DVI DL, and D-SUB. xrandr reports the D-SUB as DisplayPort-0.
In kernel versions before 4.10 I used to have to hack the i915 code as follows (in intel_hdmi.c):
@@ -849,7 +849,7 @@ static int hdmi_portclock_limit(struct intel_hdmi *hdmi, bool respect_dvi_limit) { struct drm_device *dev = intel_hdmi_to_dev(hdmi);
- if ((respect_dvi_limit && !hdmi->has_hdmi_sink) || IS_G4X(dev)) + if (IS_G4X(dev)) return 165000; else if (IS_HASWELL(dev) || INTEL_INFO(dev)->gen >= 8) return 300000;
After 4.10 came out the hack became unnecessary.