Yet unannounced Intel Pentium M processors for 533MHz processor system bus emerged for sale in Tokyo, Japan. The products come in Intel’s typical retail packages, which implies that the chipmaker has already started to ship such central processing units to various customers including retailers.

Currently Intel Pentium M processors 760, 750, 740 and 730 clocked at 2.00GHz, 1.86GHz, 1.73GHz and 1.60GHz respectively are being sold in Tokyo, Japan. All the chips are based on the core code-named Dothan with 2MB level-two cache and are produced using 90nm process technology. The processors come in mPGA479 form-factor and are intended for yet-to-be-released mobile platform code-named Sonoma and i915-series chipsets code-named Alviso which supports 533MHz Quad Pumped Bus with enhancements for mobile processors.

Intel Pentium M processors with 533MHz processor system bus also feature Execute Disable Bit security capability, a security feature that protects certain system memory data regions from insertion and execution of potentially harmful code; the technology is also referred as NX-bit and EVP and works only in conjunction with Windows XP operating systems that feature Service Pack 2. Execute Disable bit allows the processor to classify areas in memory by where application code can execute and where it cannot. When a malicious worm attempts to insert code in the buffer, the processor disables code execution, preventing damage or worm propagation. Some of Intel’s desktop, server and workstation chips already support EDB.

According to a report of Akiba PC Hotline web-site a number of stores in Tokyo are currently selling the Intel Pentium M chips with 533MHz processor system bus at various price-points. Currently Intel Pentium M processors 760, 750, 740 and 730 cost $445-$575, $300-$510, $250-$345, $210-$290, respectively.

It is unclear how Japanese enthusiasts will use the Pentium M processors with 533MHz processor system bus, as Intel’s current mobile chipsets do not support the 533MHz speed-bin, while the chips intended for Socket 479 cannot be installed into mainboards with Socket 478. Still, a Japanese web-site claims that some desktop mainboards, presumably those from DFI, based on i852GME chipset support 533MHz PSB.

Intel Corp. will officially support 533MHz processor system bus for mobile applications with its forthcoming platform code-named Sonoma that focused on bringing high-end multimedia and technology features, such as PCI Express, DDR2 memory, DirectX 9.0 graphics, high-definition audio, etc..