http://xbox.gamespy.com/xbox/microso.../594331p1.html
# CPU - Xenon's CPU has three 3.0 GHz PowerPC cores. Each core is capable of two instructions per cycle and has an L1 cache with 32 KB for data and 32 KB for instructions. The three cores share 1 MB of L2 cache. Alpha 2 developer kits currently have two cores instead of three.
# GPU - Xenon's GPU is a generation beyond the ATI X800. Its clock speed is 500 MHz and it supports Shader 3.0. Developers are currently working with an alpha 2 GPU. Beta GPU units are expected by May and the final GPU is slated for a summer release. The final GPU will be more powerful than anything on the market today; in game terms, it would handle a game like Half-Life 2 with ease.
# System Memory - Xenon will have 256 MB of system RAM. Keep in mind that this number should not be equated to typical PC RAM. The Xbox has 64 MB of system RAM and is a very capable machine.
# Optical Drive - As many have speculated, Xenon will not use Blu-Ray or HD-DVD. Games will come on dual-layer DVD-9 discs. While the media is the same as that of the current Xbox, the usable space on each disc is up to 7 GB. The drive is slated to run at 12X.
# Memory Units - Xenon will use 64 MB to 1,024 MB memory cards. 8 MB is reserved for system use, leaving a 56 MB to 1,016 MB for user data.
# Hard Drive - As many have speculated, Xenon's hard drive is optional. 2 GB of the drive will be used as game cache. The final drive size is still being determined.
# Camera - Xenon will have a USB 2.0 camera. It's capable of 1.2 megapixel still shots and VGA video. Photos can be used in-game and for gamer profiles. The camera can also be used for video chat. It's unknown if the Xenon camera will allow for EyeToy-like gameplay. Developers are currently using a simulated camera driver.
# Sound Chip - Xenon does not have an audio chip in the traditional sense. Decompression is handled by hardware, while the rest of the chores are handled by software. DirectSound3D has been dropped in favor of X3DAudio. The former was deemed too inflexible