After a Samsung monitor goes to sleep if fails to wake up requiring the monitors power cable to be pull of the DP called pulled.

This is in the logs:

[356509.261411] [drm:intel_dp_complete_link_train [i915]] *ERROR* failed to start channel equalization
[357167.172244] [drm:intel_dp_start_link_train [i915]] *ERROR* too many full retries, give up

Monitor details: Samsung S27D850T running at 2560X1440

Kernel: 4.1.5-200.fc22.x86_64

lspci:

00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) (prog-if 00 [VGA controller])
	DeviceName:  Onboard Graphics
	Subsystem: Acer Incorporated [ALI] Device 0493
	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 31
	Region 0: Memory at fe000000 (64-bit, non-prefetchable) [size=4M]
	Region 2: Memory at d0000000 (64-bit, prefetchable) [size=256M]
	Region 4: I/O ports at f000 [size=64]
	Expansion ROM at <unassigned> [disabled]
	Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
		Address: feeff00c  Data: 4182
	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
	Kernel modules: i915

for file in /sys/module/i915/parameters/*; do echo -en $file"\t"; sudo cat $file; done;
/sys/module/i915/parameters/disable_display	N
/sys/module/i915/parameters/disable_power_well	1
/sys/module/i915/parameters/disable_vtd_wa	N
/sys/module/i915/parameters/enable_cmd_parser	1
/sys/module/i915/parameters/enable_execlists	0
/sys/module/i915/parameters/enable_fbc	-1
/sys/module/i915/parameters/enable_hangcheck	Y
/sys/module/i915/parameters/enable_ips	1
/sys/module/i915/parameters/enable_ppgtt	1
/sys/module/i915/parameters/enable_psr	0
/sys/module/i915/parameters/enable_rc6	1
/sys/module/i915/parameters/fastboot	N
/sys/module/i915/parameters/invert_brightness	0
/sys/module/i915/parameters/load_detect_test	N
/sys/module/i915/parameters/lvds_channel_mode	0
/sys/module/i915/parameters/lvds_downclock	0
/sys/module/i915/parameters/lvds_use_ssc	-1
/sys/module/i915/parameters/mmio_debug	0
/sys/module/i915/parameters/modeset	-1
/sys/module/i915/parameters/nuclear_pageflip	N
/sys/module/i915/parameters/panel_ignore_lid	1
/sys/module/i915/parameters/prefault_disable	N
/sys/module/i915/parameters/preliminary_hw_support	0
/sys/module/i915/parameters/reset	Y
/sys/module/i915/parameters/semaphores	-1
/sys/module/i915/parameters/use_mmio_flip	0
/sys/module/i915/parameters/vbt_sdvo_panel_type	-1
/sys/module/i915/parameters/verbose_state_checks	Y