Introduction
You can certainly remember my Athlon Performance-Scaling article from Monday, where I showed the results of the Athlon-processor at 500-800 MHz. My first decision was to keep the technique used for overclocking this CPU under disclosure until we found an easy way for users to do it. As a matter of fact there’s a pretty convenient way of changing Athlon’s voltage and multiplier settings, but it requires a little card that’s plugged onto Athlon’s internal connector. We found out about how to overclock Athlon the tough way by comparing all the different Athlon-processors we have got here in the lab. Fortunately we don’t only have Athlons at 600 and 650 MHz, but also the Athlon from Kryotech’s Cool Athlon 800 system, which is using a higher voltage of 1.8 V rather than the other two, which are running at 1.6 V core voltage. With the details of those three CPUs we were able to reverse-engineer Athlon’s voltage and multiplier selections.
With my Athlon-Scaling article I incidentally started some kind of competition on the web about who would be the first one to publish how to overclock Athlon. Unfortunately there’s a significant number of incorrect or at least incomplete ‘How To’s available now, so that I felt forced to publish the complete story here. The last thing that anyone wants is to destroy his brand new Athlon CPU due to wrong or incomplete information. If any Athlon-owner really thinks that his system is still too slow and he’s capable of soldering SMD-parts, he’s now got the complete information required for successfully overclocking Athlon.
I still would like to point out that I strongly advise against cracking open Athlon and starting to solder around on Athlon’s PCB! Don’t go for it unless you know exactly what you’re doing! Tom’s Hardware Guide will not take any responsibility for any destroyed Athlon-CPU or system! You might still want to wait until we can supply you with a way to make this little Athlon-overclocking card that plugs onto the internal connector. This way you would not risk the CPU.
I don’t really feel too well telling a large amount of people to screw around with their Athlon-processor. Please be advised that AMD will not take any CPU back that has been opened. As soon as you removed the cover you’re on your own. In the direction of AMD, who certainly disapproves this article, I would like to point out that sooner or later somebody else would have found out and published the info, and we made sure that our Athlon Overclocking Guide is as foolproof as possible.
Athlon’s PCB
After removing Athlon’s cover, which is just as easy or painful as removing the cover from SECC1 Pentium II CPUs, you’ll find three selection areas on the backside of the PCB, and one area on the front side of the PCB, where the core chip is mounted to. Those areas consist of clusters of four slots for SMD-resistors and the programming works by letting those slots either open or bridging it with the correct resistor. Altogether there are sixteen of those slots.
The backside hosts the voltage-selection area and the main multiplier area right next to it. You’ll also find the first half of the additional frequency IDs close to the internal connector.
On the front side is the second half of the additional frequency IDs located, again close to Athlon’s internal connector.
Changing the Multiplier
You are required to take care of 12 settings for changing Athlon’s multiplier. All the 12 slots are using 1000 Ohm SMD-resistors. The first four are R155, R156, R157 and R158 on Athlon’s PCB-backside. The following picture should give you a pretty good idea of where they are. Please note that the voltage selection area is right next to it; so don’t change the wrong parts!
The next table shows you how to set the SMD-resistors for the clock speed you like.
Changing the Multiplier Continued
The next step is changing the additional frequency IDs on the backside of Athlon’s PCB, called BP_FID. The resistors are found right underneath the internal connector.
Place the 1000 Ohm (‘102’) SMD-resistors according to the following table.
Changing the Multiplier Continued
For the last cluster of resistors you’ve got to flip the PCB. You’ll find it close to the internal connector, just on the opposite side of the previous four. Again please use 1000 Ohm resistors. Don’t start with R2, which is the very left one, the cluster starts with R3!
Again, the table below should make it easy for you to do the right adjustments.
Now reconnect the heat-plate and try your newly adjusted Athlon-CPU. In the majority of cases you won’t even require a voltage change.
Changing the Voltage
You can certainly remember that we only used a slight voltage-increase of 0.05 V to 1.65 V to run our Athlon 650 at 750 MHz. Please keep this in mind and don’t overdo the voltage change. You could easily fry your Athlon!
The voltage-selection cluster is found on the backside of Athlon’s PCB. Please note that you’ve got to use 100 Ohm (‘101’) SMD-resistors for that one. Again, don’t change the wrong resistors, the multiplier-area is right next to the voltage-selection area!
The table shows you how to adjust the settings.
After finishing this procedure your Athlon should do what you want and run stably at the desired core clock. Please remember though that speeds above 750 MHz will require very good cooling!
Reminder
I can’t say it often enough, BE CAREFUL! Start this procedure only if you have experience with SMD-soldering! You require a professional heat-adjustable soldering iron with a very fine tip. Use a very fine tool to keep the SMD-resistor in place, don’t overheat the PCB, don’t scratch around on it, don’t rip off a half-soldered SMD-resistor, because it kills the PCB, and be careful that your SMD-part doesn’t stick to the tip of your soldering iron!
Don’t do it if you feel insecure in any way! Don’t do it altogether as long as you haven’t got a damn good reason to increase the performance of your Athlon. In most cases Athlon performs better than anything else anyway. Don’t do it just for fun and don’t think that it increases your pecker-size in any way. Even the crazy die-hard overclockers should have learned that by now. You ARE risking the life of your CPU! Don’t ever forget that!
Note:
You might have found out already, I mistakenly used the picture of an Athlon 600 backside and an Athlon 650 front side. Don’t look at the settings, those pictures are only used as a map to make finding the selection areas easier. The tables show the correct settings.