PC-Doctor cannot test some devices in DOS unless you install the device driver first. If a PC-Doctor diagnostic test reports N/A for a device, ensure that the appropriate device driver (or enabler) is installed and run the test again. In many cases PC-Doctor can provide system information for devices even if it cannot test them. The categories PCI Info, PnPISA Info, PCMCIA Info, and DMI Info on the Hardware Info menu report information about devices whether their drivers are installed or not.