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Upgrading a Pentium- or K6-based PC

Remove the Old CPU

Turn off your PC, but leave it plugged in--a safeguard against static damage. To reach the CPU, you may first have to move cables or add-in cards. Disconnect the power cable to the CPU fan, if any. The fan or heat sink may have to come off separately.

Note which corner of the CPU has a small diagonal cut and (usually) a dot. That is pin 1. Put a masking tape mark near pin 1 on the motherboard to ensure easy insertion of your new CPU.

Touch a metal part of the case (to ground yourself) and with your other hand gently lift the CPU-release lever. Carefully pull the processor straight out of its socket.

Insert the New CPU

Remove the upgrade processor from its protective packaging and carefully insert it into the socket. Make sure you have pin 1 of the CPU well aligned with pin 1 of the socket. If it's aligned improperly, turning on the system's power may ruin your new CPU.

Press the CPU down firmly into the socket with your finger and push down the locking lever. Connect the CPU's fan to its power connector.

Set the Motherboard Jumpers

To get maximum performance from your processor upgrade, you must set your motherboard's bus speed to 66 MHz. In addition, you must set the motherboard's clock multiplier to its maximum value, usually 3.5X.

Although some motherboards clearly mark the setting, you'll probably need to check your board's manual. And some newer motherboards don't have jumpers, in which case the new CPU upgrade should set things up on its own.

Don't put the cover back on your PC until you're sure things are working correctly. If everything seems okay, run your applications to make sure. But if nothing happens when you turn it on, power down and check to see that the CPU is inserted properly. If you still have problems, don't hesitate to call tech support.