My system has worked perfectly for a year now with my old Dell 24” 1920 x 1200 resolution, flat-screen monitor with a DVI connection. I just bought a new LG 34UM95 wide-screen monitor. If I use the HDMI input on the new monitor (Mini-DisplayPort to HDMI cable), everything works flawlessly—but I’m stuck with a 30Hz screen refresh rate that is no good for games. However, if I use the DisplayPort 1.2 input (Mini-DisplayPort to DisplayPort cable), I can get a 60Hz refresh rate, but the system crashes (auto-reboot, no blue screen) the moment any application switches into full-screen graphics mode.
I am running two Radeon 7990s in CrossFireX (4 GPUs). If I disable CrossFireX, then I can use full-screen graphics through the DisplayPort input at 60Hz. If I enable CrossFireX, then the system crashes when switched into full-screen graphics. It makes no difference what the screen refresh rate is set to (30, 50 or 60Hz), or the resolution (native 3440 x 1440 or scaled down), or which driver is installed (Catalyst 14.4 or 13.12), or if anything is overclocked or not: If CrossFireX is enabled to the DisplayPort input, the system immediately crashes (reboots) the moment full-screen graphics is turned on.
The system event logs don’t give any useful information. A “Critical” “Kernel-Power” error message is logged that says, “The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly.”
I also tried different cables and different outputs on the 7990s. Same result.
Anyone have an idea what I can do? I’d really like this monitor, but I’m not going to remove my second 7990 graphics card.
Two Radeon HD 7990s in CrossFireX.
AMD Catalyst Driver Version, and Driver History
Catalyst 14.4 and 13.12
Windows 8.1 x64
Motherboard or System Make & Model
Asus Rampage IV Extreme
Display Device(s) and Connection(s) Used
Monitor: LG 34UM95 (3440 x 1440 native resolution); Connection: DisplayPort 1.2 (Mini-DisplayPort to DisplayPort cable) and HDMI (Mini-DisplayPort to HDMI cable).
Applications and Games
All applications running in full-screen graphics mode fail.
CPU: Intel 4930K @ 4.4GHz (overclock on CPU makes no difference)
Motherboard BIOS Version
American Megatrends version 4403
System Memory Type & Amount
32GB Corsair, DDR3 @ 1866MHz
SSD, HDD, Blu-Ray Drive, lot of fans in water cooled system
09:03 PM by