From IGN's site
Sony entering any market must be an ominous thought for any competitor, even one with Nintendo's lock on the handheld game. Sony announced the PSP (PlayStation Portable) at last year's E3 and it immediately became one of the most anticipated pieces of gaming hardware for 2004.
The brains of the PSP come in the form of twin MIPS R4000 32 bit processors running at max 333MHz. One of these units is referred to as the Media Engine, and is to be used for sound, movies and I/O management. The system is expected to feature 8MB of main memory with a bandwidth of 2.6 Gigabytes per second along with 2MB of sub-memory for the Media Engine.
Outside of the CPU and main memory, the system will of course include a graphics processing unit (GPU). The GPU is made up of a Rendering Engine and a Surface Engine and has access to 2 Megabytes of VRAM with a bandwidth of 5.3 Gigabytes per second. The hardware will include support for traditional polygons as well as curved surface primitives along with such things as clipping, morphing and more, freeing up software from having to deal with these. Sony claims a theoretical polygon performance of 33 million polygons per second.
The system's UMD (Universal Media Disc) optical disk format has also been clarified a bit. A UMD is a 60 millimeter dual layered disk that can store up to 1.8 Gigabytes of data. Transfer rate for the reader unit is 11 Megabits per second, which is twice the transfer rate of a standard DVD system.
Multimedia support is big for the system. Sony announced MPEG4 support at E3, and now they've gotten a bit clearer, revealing that the PSP will use the AVC decoder, which has a high encoding rate. This will allow the UMD to store up to two hours of DVD quality video. Sound is also taking a high place on the system's feature list. The PSP will feature reconfigurable DSPs which can be rewritten allowing for support for the latest sound technology. Sony announced compatibility with the ATRAC3 plus format along with AAC and MP3. In addition, the system will support playback of 3D and 7.1 channel sound. On top of all this is Wireless LAN. The system will include as standard IEEE802.11 wireless LAN.