My Windows 11 desktop powers back on after sleeping—the motherboard lights up, fans spin, and I can hear it click—but neither monitor displays a usable image. The main DisplayPort monitor initially reports no signal, then wakes to a black screen. The keyboard and mouse are also unresponsive: Caps Lock does not toggle, and Win + Ctrl + Shift + B has no effect. I have to hold the power button to shut the system down and restart it.
The system uses an ASRock X670E Taichi motherboard, Ryzen 7 7800X3D, RTX 4090, a 4TB NVMe SSD, and 96GB of Corsair Vengeance DDR5-6000 CL30 memory in a 2x48GB configuration. The memory is installed in the recommended slots and normally runs at 6000 MT/s with XMP enabled. There is no overclocking, PBO, Curve Optimizer, or undervolting.
The primary monitor is connected to the RTX 4090 by DisplayPort, while a second monitor was connected through the motherboard's USB-C output. I tested different cables and monitors, disconnected the second display entirely, and still had the same problem with only the main monitor connected. I also tried updating Windows 11, the BIOS, NVIDIA drivers, and chipset-related software, but nothing resolved it.
The Balanced power plan is set to sleep after 15 minutes. The hard disk timeout is 20 minutes, Link State Power Management is disabled, Fast Startup is disabled, and Deep Sleep is disabled in the BIOS. This began after I temporarily changed the sleep timeout to five hours and later changed it back to 15 minutes. The computer had worked normally for about two years before this, but it now fails to resume every time it sleeps.
What could cause the entire system to become unresponsive during sleep resume? Could this be related to Windows power settings, ACPI, BIOS behavior, memory stability, the GPU, or PCIe power management?
3 Answers
Because the keyboard and mouse stop responding too, this looks like a failed sleep-resume process rather than just a DisplayPort or monitor problem. First test with XMP disabled so the memory runs at its default speed. High-capacity DDR5 at 6000 MT/s can be stable during normal use but still fail during low-power transitions. If sleep works at stock memory settings, that points toward memory training or platform stability. Also make sure the AMD chipset drivers are current.
It is worth testing HDMI temporarily instead of DisplayPort. DisplayPort link renegotiation can occasionally cause a black screen after sleep, although the fact that Caps Lock and the input devices do not respond suggests the system may be hanging before Windows finishes resuming. If HDMI makes no difference, the display connection is probably not the main cause.
Reset Windows power plans to their defaults before changing more BIOS or hardware settings. Open an elevated Command Prompt and run `powercfg -restoredefaultschemes`, then restart and configure the 15-minute sleep timer again. A corrupted or inconsistent power-plan configuration could explain why the problem appeared after changing the timeout.
The BIOS update had already reset the memory to its default 4800 setting, and the wake failure still happened. I enabled XMP again afterward, but there was no change. I’ll continue testing other causes.