Overclocking the Athlon processor
As you probably know by now, AMD has implemented a multiplier lock on their Athlon "Thunderbird" and Duron processors. This is nothing new for the seventh-generation processor, previous versions of the Athlon required soldering resistors or using a "golden fingers" device to adjust the CPU multiplier and voltage (although newer Athlon motherboards allow voltage adjustments via System BIOS).
In fact, to this day, Golden Fingers devices like those sold by Outside Loop Computers can be used to adjust both parameters on Slot 1 Thunderbird CPUs.
With AMD's transition to the Socket A interface however, attaching an overclocking card to your CPU obviously isn't possible - a physical connection to the CPU doesn't exist. As a result, overclocking enthusiasts have been searching for ways to get around the multiplier lock.
Solving the mystery
Last month, Tom's Hardware Guide published the solution
to the "multiplier mystery" - connect the bridges!
As you can see in the picture below, two sides of AMD's Socket A processors contain copper bridges, labeled L1-L7. Each group of these bridges determines such CPU settings as core voltage and the clock multiplier.
If you have a locked Athlon or Duron processor, the bridge you'll need to adjust to unlock the processor is L1. Traditionally a conductive pen is used to adjust the bridges, but recently Wesley's Computer Hardware Zone published their guide with step-by-step instructions using a cheaper tool: a pencil!
As absurd as it sounds, the solution has apparently worked flawlessly for many people. With the clock multiplier unlocked, motherboards with built-in multiplier adjustment such as the Abit KT7 or ASUS A7V can then be used to overclock the CPU. (For those of you without either motherboard, the clock multiplier can be adjusted via the L3 and L4 bridges)
But what if there was a way to easily determine if an Athlon or Duron processor was locked before you purchased it? Read on to find out how!