Cirrus Logic makes the EP7312 ARM processor with digital audio interface. Check out this application note, which discusses configuring the 7312 for digital audio for the "MP3 market."

The venerable Crystal Semiconductor CS8900A provides 10 megabit ethernet support. HomePNA support is provided via a chipset from BroadCom. The BCM4210 provides the MAC (Media Access Control) and PHY (physical layer) for the HomePNA network interface. The BCM4100 provides the analog front-end for HomePNA. The Micron MT48LC4M16A2 is a 64Mbit (8 Megabyte) 16-bit SDRAM chip, and there are two of them on the board. Note the set of empty pads. These pads are for a higher density part than the two 64Mbit SDRAM chips. It's likely that they are for a MT48LC4M32B2 128Mbit (16 Megabyte) 32-bit SDRAM chip. Depending on how the addressing is handled on the board, it might be possible to add an additional part to increase the total system RAM to 32 Megabytes. However, it is perhaps more likely that this was meant as an option for manufacturing, designed with the parts shortages the industry was experiencing at the time of design. Manufacturing could choose to stuff either the two 64Mbit parts, or the one 128Mbit part, depending on whichever was cheaper or more available.

Just in case there was any doubt about which operating system runs on the AudioTron. Those grayed out areas were Microsoft serial numbers. I didn't feel like having anything traced back to my mother's maiden shoe size, so you get gray bars. :) Note under the sticker, pads for what is probably an addition flash ROM chip.

There are two headers on the main board which are not connected to anything. It's quite likely that these are debug headers (perhaps an asynch serial port, and quite likely a JTAG port) and/or expansion headers.

The power supply section of the mainboard, and the off-board transformer and EMI filter. The transformer delivers AC to the mainboard where it's full-wave rectified and smoothed with the large capacitor at the top of the photo. The National Semiconductor LM2598-3.3 is a 3.3V 1A simple switcher. It's likely that L5, D4, and the capacitors next to U9 are for the 3.3V supply. It seems there's another switching supply nearer the top of the board, comprised of L4, U7, D1, and the capacitors near U7.

Voyetra, Turtle Beach, AudioTron, and likely a whole bunch of other things are probably trademarks of their respective owners. I do not try to lay claim to any of them!