Sony VAIO laptop reboots after putting it into sleep mode | Joachim De Zutter
Laptop model: VPCEB4M1E

Steps to reproduce the issue:
1. Press the power button.
2. Log in to Windows 7 Home Premium.
3. Press the power button.
4. Wait until the color of the blinking light of the power button becomes orange.
5. Press the space key or power button.
(now the laptop either reboots or goes out of sleep mode)

The hardware issue was resolved by improving the CPU cooling by the heat pipe.