Return To Castle Intel: 16 Years Of Motherboard History

Return To Castle Intel: 16 Years Of Motherboard History
One thing you’ll notice on the really old boards is that some of the SIMM slots closer to the board edge are angled 45 degrees. This was due to chassis height restrictions for items like the hard drive or power supply. The real nugget here is the “OverDrive Ready” stamp on the CPU socket (Socket 4), a feature so ancient that it stumped our first set of Intel engineers. Socket 4 supported a 5V connection and only worked with the Pentium 60 and 66 chips. Socket 5 (3.3V) would later support the Pentium 75 to 133 and used staggered pin rows. The Pentium OverDrive chip used a clock doubler to take the speed to 120 or 133 MHz on Socket 4 systems. The net result was slower than a true 120 or 133 MHz product, but it was the poor man’s answer to a system upgrade. There were also OverDrive chips for Socket 5, Pentium Pro, and, most famously, the 486, which allowed a Pentium core to run on a 486 platform with somewhat hit and miss results.