The Intel Core 2 Quad Q9400 was a desktop processor with 4 cores, launched in August 2008. It is part of the Core 2 Quad lineup, using the Yorkfield architecture with Socket 775. Core 2 Quad Q9400 has 6 MB of L2 cache and operates at 2.666 GHz. Intel is making the Core 2 Quad Q9400 on a 45 nm production node using 456 million transistors. The multiplier is locked on Core 2 Quad Q9400, which limits its overclocking potential.
With a TDP of 95 W, the Core 2 Quad Q9400 consumes a good deal of power, so decent cooling is needed. Intel's processor supports DDR1, DDR2 and DDR3 memory with a dual-channel interface. For communication with other components in the system, Core 2 Quad Q9400 uses a PCI-Express Gen 2 connection. Although the processor doesn't come with integrated graphics, certain motherboards with compatible chipsets can provide this capability.
Hardware virtualization is available on the Core 2 Quad Q9400, which greatly improves virtual machine performance.