Intel Pentium Pro

The Intel Pentium Pro was released in 1995 while the original Pentium line was still active, and introduced the P6 architecture. Later and even current x86 processors are based on the P6 architecture, with significant changes integrated over the years. Pentium Pros were first made with a 500 nm process and incorporated 5.5 millions transistors.

They were available as 150, 167, 180 and 200 MHz parts, and 133 MHz prototypes exist, while 200 MHz models can often be overclocked to 233. This processor uses the Socket 8.

The Pentium Pro targeted the Server Market and was thus very expensive as are usually the Xeon Processors nowadays.

Intel KB80521EX150 — A 150 MHz Pentium Pro, Early without "Pentium Pro" Text (SY002). Back. Malaysia, 1995 Week 36.

A 200 MHz Pentium Pro (SL22T). Back. Malaysia, 1998 Week 11.

A 200 MHz Black Pentium Pro, with 1 MiB L2 Cache (SL25A). Back. Philippines, 1998 Week 13.

Intel KB80521EX200 — A 150 MHz Pentium Pro, Early without "Pentium Pro" Text (SY002). Back. Malaysia, 1995 Week 36.

A 200 MHz Pentium Pro (SL22T). Back. Malaysia, 1998 Week 11.

A 200 MHz Black Pentium Pro, with 1 MiB L2 Cache (SL25A). Back. Philippines, 1998 Week 13.

Intel Pentium Pro Keychain — A Keychain with a Pentium Pro Processor and Cache Dice.

The Pentium Pro is suceeded by the Pentium II in 1997.

Operating System Support

A Pentium Pro will by itself not prevent any x86 Windows until 7 from running. Windows Vista and 7 officially require a 800 and 1 GHz CPU, but can actually work on a Pentium Pro regardless of the frequency.
- They however require the motherboard to have some ACPI compliance, and we are not aware of any Socket 8 Motherboard fulfilling the requirement. Thus, the only way to run Vista or 7 on a Pentium Pro is to do it on a Slot 1 Motherboard using a Socket 8 -> Slot 1 Adapter, which are very difficult to find, even though there may be some hope of finding them more easily in the future as we are aware of people having reverse engineered such Slotkets and even own a couple of these clones. On such setup, it is as easy to run Vista or 7 as it would with a Pentium II or III.
- Even with a compatible Graphics Card, there is no way to enable Aero as this will crash the Desktop Window Manager, presumably due to the lack of MMX.
- Similarly, the Windows Experience Index assessment will also stop quickly after it started, claiming to be unable to complete.
Windows 8 and later are no gos as it is not even possible to install them on Pentium IIIs.
The Pentium Pro is still supported by the Linux Kernel, and Linux Distributions still supporting x86 usually require the Pentium Pro as the minimum, and will work if other requirements like having enough RAM are met. An example is Debian 12.