Fixing the FIC

SUMMARY: A step by step guide to modifying the FIC and AMD’s Duron to accept multiplier overclocking.

Almost as soon as I landed at JFK after a three week vacation, Ed calls me and tells me to heat up the soldering iron – we are going to “Duronize the FIC”. Now, considering I have a six hour time difference and 12 hours of wing time, I have no idea what he’s talking about.

Shift forward a day: Ed’s got a Duron and an AZ11 courtesy of PCNut. I have surfed around and read up on how to get the Duron unlocked and running – the AMD and FIC mods are explained (somewhat) on other sites. What’s missing is a real “How-To” that ordinary folks can follow, and so Ed and I sat down and proceeded to make the required mods. What follows are the steps required with detailed pics to get your Duron working on a FIC AZ11.

We read the following Duron overclocking articles to get a summary of what’s required:
Hiroji’s Duron 900 (@600)
Toms Hardware

Next, after trying to absorb what, in my mind, is some really obtuse information, understand that you have four things to do:

  1. Determine if your Duron is locked or unlocked: If locked, you will have to use a silver pen to unlock it;
  2. Adjust the Duron with the silver pen to support the voltage you need to get it stable;
  3. Cut traces on the rear of the FIC AZ11;
  4. Solder jumpers or dip switches on the FIC AZ11 to adjust the Duron’s multiplier.
Step 1 – Unlocking the Duron

To change the multiplier through the motherboard, the motherboard must send a signal to the CPU to change the multiplier. Any signal from the motherboard to change the multiplier from its rated speed goes through the L1 bridges. To “lock” the CPU, AMD breaks the L1 bridges, so these motherboard signals can’t get through. No signal, no change. So if the bridges are broken, you have to reconnect them so your other changes can work.

When we read the articles about this, it sounds really simple; you get this pen and sort of write on the Duron and it is unlocked. HA! Take a look at the picture below:


The broken lines are underlined in red – this is how AMD sets the parameters for each chip.

The railroad spike in the picture is the head of a pin. Not a big pin either, just an ordinary pin. AMD uses a laser to cut the lines in half which determine what the chip will become. In this case, what you see is an unlocked Duron 600 (L1 lines are not broken). If the lines on L1 were broken, you would use the silver pen to reconnect them to unlock the multiplier.

The problem is the so-called “micro-tip” of the pen is like doing brain surgery with an axe. First effort was trying to get the stuff inside the pen to flow; after some time, I got it to work by sticking a pin into the tip and squeezing a blob of connecting gop onto the pin. Even this gop was too much.

The best way to connect the dots is to put some of the connecting fluid on a knife-edge and connect any severed line in the L1 bridges.

Look at the picture above again and you will understand it’s delicate stuff – not brain surgery, but unless you are really eagle eyed, a magnifying glass is part of your kit.

If you make a mistake, don’t worry, just rub away the material.

You could hardwire any multiplier change by working on the L3, L4 and L6 bridges. You can find the appropriate settings on Toms Hardware.

However, to do that, not only do you have to make connections, you also have to break them. There’s no way you can avoid breaking at least one of these, and realistically two or three.

Take a look at that pin again. Do you really want to try breaking copper bridges that small? It’s nowhere near as easy as cutting the traces on the back of the motherboard, and you have to be delicate to prevent damage to the CPU. Basically, you chip away at it a little at a time, a task all who have tried have called really tough.

Operating on the motherboard is far easier and safer, and gives you far more flexibility.

Step 2 – Adjusting the Duron’s Voltage


Not a lot of wiggle room.

Do the same with line L7 – this is where the CPU’s voltage is set. For this pass, we connected all the dots to get it to 1.85, figuring we were going to go all out with this setup. If you want to use less voltage, see Toms Hardware for the settings.

You can also do a mod to the FIC AZ11 so you can change voltage settings with a dipswitch, but after looking at what’s required in the way of incredibly fine soldering, I don’t think it’s the recommended approach. The best description on doing this is on Hiroji’s Duron 900 (@600). I heard that FIC will be releasing a BIOS with voltage changing, but don’t count on it.

Step 3 – Cutting The Rear Traces

Shown below is the Socket A connectors on the back of the motherboard. Highlighted in red are the traces that must be cut.

Rear Socket

View of the Socket A from the back.

Cut the following four traces on the back of the motherboard with a sharp knife (an Exacto knife is perfect).

This is the easiest step. Here is a detail shot showing the end result:

Rear Traces

Of all the mods, this is the easiest.

Just make sure you found the right traces and cut as shown in the left hand picture. The area bracketed in red gives you an idea of the working area you have. You don’t have to dig deeply into the board, just enough to cut the traces.

Step 4 – Soldering Dip Switches

Side View

The two areas are next to the Socket A.

Shown above are the two areas where you have to add switches or jumpers which enable you to change the Duron’s multiplier. I have used three dipswitches to do this because you can easily get these at Radio Shack (Catalog # 275-1301B).


Solder four wires onto points R238, R237, R251 and R250.

They are located near the edge of the motherboard nearest the socket A, a little above and to the right of it. The first set of switches are the easiest to solder – there are only four pads and the solder point are relatively far apart (see pic below).

4 Pads

Solder wires to the four outermost points.

I used some very fine wire to do this – the larger the diameter, the more difficult it will be to keep it within the solder pads. As you will see in PART II, the solder pads get much closer together. Use a fine point soldering iron of about 30 watts – you don’t need a lot of firepower here, just enough to melt the solder on the pad into the wire. The finished product is shown below:

4 Pad Wired

The numbers in red correspond to AMD’s numbering for FID 0, 1, 2, 3.


Now this gets a bit more crowded. In this area there are 12 solder pads. Leave enough wire so that you can solder the end to the dipswitch and have enough room to locate the dipswitch circuit board in a convenient location. Solder the back row first, then work towards the edge of the board, otherwise you will be soldering through a forest of small wires.

12 Pads

Small and crowded – you need a fine soldering tip to work here.

After you have this done, it looks like Medusa – lots of snaky little wires wiggling around. The last step is now to attach all the wires to dipswitches so you can easily adjust the Duron’s multiplier.

12 Pad Wired

The numbers in red are used in wiring up the dipswitch.


You can buy a small chunk of circuit board from Radio Shack to hold the dipswitches. As the pic below show, I have used three of them (note that you can accommodate all functions with only two dipswitches). You don’t need 8 position switches, but since that’s all they had in stock, we used these; you’ll only need four switches on each one.

Take your time doing this; it can get confusing.

This is what you do with the wires you soldered:

Dip Switch Wiring

Very patiently and slowly connect the wires to the posts.

Take the wire from the “A1” position as indicated in the TWELVE POINTS pic above and solder it to the dipswitch pin corresponding to “A1“. Then “A2” etc.

I marked the back of the small PCB board with the switch positions to avoid any confusion from working front to back.

Note that the two dip switches next to each other share a common set of wires – labelled “B“. This is the middle row of the TWELVE POINTS wires.

PCB Back

Bending the pins holds the switches in place while soldering.

Bend the dip switch pins at the rear of the circuit board so that the middle row pins touch each other; then solder the middle row wires onto the joined pins.

After you finish with the twelve wires, do the same with the four wires as shown below.

Connect “0” to dipswitch postion “1”, “1” to dipswitch position “2” etc.

NOTE: The numbers 0, 1, 2, 3 correspond to AMD’s numbering scheme, which starts counting at 0 rather than 1, these correspond to:

Dipswitch 1 = FID 0
Dipswitch 2 = FID 1
Dipswitch 3 = FID 2
Dipswitch 4 = FID 3

4 Pad Wired

0” to dipswitch 1, “1” to dipswitch 2, etc.

Last, solder one wire to the four pins labelled “Ground” and solder the free end to a ground position on the motherboard; we used the ground pin on the PS2 connection, shown below.

PS2 Ground

The PS2 ground is easy to find and solder.

The pic below shows the finished product. I have not fixed this to anything yet as we are experimenting with this setup, so it’s not in a case.

Dip Switches

The red dots show the switch positions for 800 MHz; each red dot corresponds to where you would push down on each switch.


The following table lists all dipswitch combinations to set the Duron’s multiplier for specific speed settings. A refers to the single dipswitch at the bottom of the circuit board, B to the middle dipswitch and C to the topmost dipswitch.

Note the symmetry: Dipswitch A and B are set exactly the same while Dipswitch C is the mirror opposite.


We hope you find this useful and clear – drop us a line for any clarifications or comments. We’ll be posting some benchmarks soon.

Email Joe

Email Ed


If you are more adept at soldering, the TWELVE POINTS solder pads can be de-soldered. Holes are drilled through the board to accept jumpers, so if you have access to these components, it is possible to do a much nicer job than described here. My pal Dave at GenX Tech pointed this out to me and even gave me a part #:


So if you have the time, you can probably get these from somebody like Digikey and do a really pro mod to the board. GenX Tech is doing this mod and sells the board along with an unlocked Duron as a package.

We’d like to thank Humphrey Chen and PCNut for providing us with the Duron and AZ11 for this article.

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