Specifications

Computer Architecture and Maintenance (G-Scheme-2014)

The 66MHz OverDrive processor that replaced it consumes a maximum 2.7 amps

(13.5 watts), including about 1 watt to drive the fan. Even the original 60MHz Pentium

processor consumes up to 2.91 amps at 5V (14.55 watts). It might seem strange that the

replacement processor, which is twice as fast, consumes less power than the original,

but this has to do with the manufacturing processes used for the original and

OverDrive processors.

Although both processors run on 5V, the original Pentium processor was created

with a circuit size of 0.8 micron, making that processor much more power-hungry than

the 0.6-micron circuits used in the OverDrive and the other Pentium processors.

Shrinking the circuit size is one of the best ways to decrease power consumption.

Although the OverDrive processor for Pentium-based systems draws less power than

the original processor, additional clearance might have to be allowed for the active

heatsink assembly that is mounted on top. As in other OverDrive processors with built-

in fans, the power to run the fan is drawn directly from the chip socket, so no separate

power-supply connection is required. Also, the fan is easy to replace should it ever fail.

Socket 5

When Intel redesigned the Pentium processor to run at 75MHz, 90MHz, and

100MHz, the company went to a 0.6-micron manufacturing process and 3.3V operation.

This change resulted in lower power consumption: only 3.25 amps at 3.3V (10.725

watts). Therefore, the 100MHz Pentium processor used far less power than even the

original 60MHz version. This resulted in lower power consumption and enabled the

extremely high clock rates without overheating.

The Pentium 75 and higher processors actually have 296 pins, although they plug

into the official Intel Socket 5 design, which calls for a total of 320 pins. The additional

pins are used by the Pentium OverDrive for Pentium processors. This socket has the

320 pins configured in a staggered PGA, in which the individual pins are staggered for

tighter clearance.

Several OverDrive processors for existing Pentiums were available. These

usually were later design chips with integral voltage

regulators to enable operating on the higher voltages

the older chips originally required. Intel no longer sells

these; however, companies such as PowerLeap do still sell

upgrade chips for older systems. Figure. shows the

standard pinout for Socket 5.

Prepared By – Prof. Manoj.kavedia (9860174297 – 9324258878 ) (www.kavediasir.yolasite.com)