As soon as you lay eyes on the Killer, you know this is no ordinary network interface card. Other than the RJ45 jack accessible on its mounting plate, there is nothing about the Killer that says it's a standard NIC.
The card is built upon a dark colored PCB and is adorned with a massive, jagged "K" heatspreader. The heatspreader is attached to the card with four screws, and when tight, it makes contact with the on-board processor and custom FPGA. Throughout our testing, we found that the headspreader doesn't get all that hot, and we suspect its large size is more of a decoration than a necessity. Something not clearly visible in these pictures are a handful of red LEDs that blink when the card is receiving power.
On the surface, the card seems relatively complex, especially compared to an ordinary run-of-the-mill NIC. There are multitude of traces and surface mounted components visible just by quickly inspecting the card. The backside in particular is especially dense. And when disassembled, it become clear why.
The Killer NIC does not have a typical network controller on-board that sends a majority of the network processing to the host CPU. Instead, the card is equipped with a Freescale MPC8347E communications processor, a Xilinx Spartan FPGA, a Broadcom GigE PHY, 64MB of RAM, an embedded Linux distro and USB controller / port. The 400MHz Freescale processor used is part of the company's PowerQUICC II Pro family, which is designed for a multitude of communications applications like ethernet routers, switches, wireless LAN (WLAN) equipment, network storage, and network appliances, among others. The Xilinx Spartan FPGA is a low-cost, programmable gate array that contains Bigfoot Networks' proprietary technology. At this point, there are no plans for a custom ASIC. The 64MB of RAM on the card works in conjunction with the processor and FPGA for caching and for running specialized applications, dubbed "FNApps". FNApps can be executed by the card's processor, and can read and write data to a flash drive or external HD connected to the card's USB port.
The combination of an on-board processor and RAM, in conjunction with the Killer's ability to run applications on its embedded version of Linux independent of the host system is why we referred to the Killer as more of a "system on a card" than a beefed up NIC in our introduction. The complexity of its design and wealth of integrated components is also why this card is relatively expensive when compared to most other NICs however.