What people usually mean when searching for "CPU drivers" are the for the motherboard that the CPU is installed into. Step 1: Identify Your Motherboard (Not the CPU) Drivers depend entirely on your motherboard's brand and chipset (e.g., Intel P35, G41, Nvidia 780i). To find this:
The Intel Core 2 Duo E8400 is a CPU (Central Processing Unit). CPUs themselves do not require separate drivers to function. The operating system (Windows, Linux, etc.) handles the CPU automatically. You cannot "download a driver" for the processor alone.
There is no "Intel Core 2 Duo E8400 driver" file. Focus on your motherboard’s chipset driver instead. If everything works (network, sound, display), you already have the right drivers.