Hello everyone, this is my first instructable, but I use this site all the time and I'm glad I'm finally able to give something back.

A couple of years ago I got an old Cisco PIX506e to use as firewall for my home network.
This is a really nice equipment and even if they are a bit complicated to configure, they are very reliable.

Well, about a month ago my PIX stopped working ... a little troubleshooting indicated that the power supply was dead.

I looked around but I was unable to find any supplier in Argentina (where I currently live), and while i could get one off EBay for about U$D 20 the shipment to South America would increase the cost considerably (not to mention the Custom's Fees once in here)

So, I started looking for alternatives.

I check with a local Radio/TV repair store and they could look into fixing it, but I would have to pay a "diagnostic fee" of $40 (about U$D 10) in order for them to tell me IF they could repair it (and for how much).

I might still take it to repair, but I wanted a cheaper solution.

This instructable will show you how I adapted an old "AT type" Power Supply from a discarded computer to power a Cisco Pix 506e.

I'm describing what I done (except noted) and what it worked for me, to the best of my abilities and as much as I can remember.
If you want to follow this instructions do it at your own risk.
Don't hold me responsible if you hurt yourself, ruin your equipment, burn your house, or cause a rift in the space-time continuum .

Step 1: The power supply

I opened the PSU hopping to find a component obviously bad (so I could just replace it and move on), but there was nothing that I could detect as bad.

The exterior of the PSU was a lot more helpful, it clearly stated what the 8 pins were for:
      Ground      Ground      Ground      +5v
      ON/OFF      -12v           +12v         +5v

 5v     4   A
12v    1   A
-12v   0.1A

When I found this, I realized that this voltages and Amperages are within the range supplied by an AT PSU, and I happened to have one laying around.

My friend Google pointed my to this site  where they confirmed my suspicion.

So it was now time to do it.

<p>cheap dc power supply 12v,5v,3.3v from computer power supply<br> More At<br> http://dailytwocents.com/cheap-dc-bench-power-supply-computer-power-supply/</p>
wow, when you said a firewall i wasnt expecting there to be almost a whole computer in there!<br>great and simple fix, im glad it worked out as well as it did!<br>good job!
Well, Its more of a computer than what most will realize, this unit has a Celeron processor, a wooping 32mb DRAM (the old SIMs from XP PCs) with an extra slot to expand it, and a flash memory of 16 MB :-( <br>One of my upcoming projects is to upgrade it with a P3 and 128MB ram, and probably upgrade the OS as well ...
well ive got a few pga370 cpus and 1 128mb sticks of sdram if you want it, i sold the motherboards that were compatible anyways.
*2 128mb sticks.
yeah sure i'm interested ...

About This Instructable


3 favorites


Bio: At the age of 6 I disassembled my mother's blender ... and somehow I managed to convince my folks not to kill me :-) From that ... More »
More by marianok: Replacing the Power supply for a Cisco Pix 506e
Add instructable to: