IBM RT PC Problem Determination Manual page 28

Step 2. System Inactive
Problem Determination Guide
1-6
If the system is on, but appears inactive and will not respond to the
keyboard:
1. Turn off the system.
2. Wait about 1 minute.
3. Turn on the system.
4. After power-on self-test (POST) has completed, sign on the
system.
CAN YOU USE YOUR SYSTEM NOW?
YES Continue with your normal operations.
NO Go to "Step 2. Diagnostics" on page 2-9.