Windows 11 Runs at 2 FPS for Several Minutes After Startup

Eight gigabytes is usable for Windows 11, though it can be tight with a lot of startup software. Check Task Manager immediately after boot and look at the actual memory, disk, CPU, and GPU usage rather than assuming RAM is the cause. A clean boot can also help identify a third-party service that is delaying startup.

Because even the Windows installer is sluggish, test outside the installed operating system too. Try the installer with the laptop on AC power, check whether the BIOS setup screens respond normally, and update the BIOS and firmware. If the installer itself remains unusable while Linux is smooth, a Windows-specific graphics or storage driver is possible, but firmware or hardware compatibility still needs to be ruled out.

Run a full memory test, but low capacity by itself would not normally cause five minutes of extreme lag, and failing RAM can cause crashes or corrupted files rather than just a predictable slow startup. Also check the SSD’s health and SMART data with a drive-monitoring utility. If the SSD is intermittently stalling, Windows may appear frozen while Linux happens to behave better.

The fact that a fresh Windows installation has the same problem makes ordinary software clutter less likely. Since Linux runs normally, I’d focus on Windows drivers—especially chipset, storage, graphics, and power-management drivers. Install the Lenovo drivers for that exact X390 Yoga model, and compare behavior in Safe Mode. If it is smooth there, a driver or service is probably involved.