ACPI/VPC2004 is the hardware ID of an unknown device on my lenovo laptop that I have recently fixed. Once I formatted and installed windows 7 it was a device without driver in the "unknown devices" section of device manager. The device when installed correctly is the "Lenovo ACPI-Compliant Virtual Power Controller"
ACPI VPC2004 driver is found during the installation of certain drivers from lenovo.
Unknown Device with device ID "ACPI/VPC2004" This solution worked with Windows Vista and 7
Fixing the ACPI/vpc2004 driver
- Update and install "Lenovo Energy Management" software (comes with a driver, HAS to be from lenovo for your machine)
- Restart and check device manager to see if your device is still unknown