After launching a game, a browser tab, and another application, the computer became extremely slow and stopped responding normally. Task Manager would not open, and although Alt+F4 closed some windows, the system remained sluggish. I eventually shut the PC down using the power button. Since then, it starts directly in the BIOS instead of loading Windows. The motherboard is an ASUS ROG Strix B550-F Gaming WiFi. What should I check to determine whether this is a boot-drive or hardware problem, and is there a way to fix it?
2 Answers
Try saving and exiting the BIOS, then restart the computer. If it returns to the BIOS again, check whether your Windows drive is detected under the storage or NVMe information. Also look at the boot order and make sure Windows Boot Manager for that drive is selected first. If the drive is missing entirely, power the PC down and reseat the M.2 drive or its cables. A drive that suddenly disappears may be failing.
In the BIOS, check the boot menu and confirm that Windows Boot Manager is present. If it is present, select it manually and see whether Windows loads. If it is not listed, the system may have lost the boot entry or the storage drive may not be detected. Avoid reinstalling Windows right away, since that could overwrite your files; first confirm whether the drive appears in the hardware information and test its connections.

Restarting does not help—it keeps opening the BIOS instead of Windows.