See-Through PSU - Modjitsu #26

There's not much joy in paying for something kick-arse - like, say, a muntingly potent 400w PSU - and not being able to see the good bits inside. No sir! Ron Prouse takes us through a PSU mod that shows us the goods, which unfortunately, look fairly dull, so he shows us how to add a little light.

ABOVE: The fiddler-than-a-case-window PSU window.

Recently several companies began marketing translucent, plastic PSU covers designed to totally replace the cover plate. The product concept is cool, but the examples I have looked at have 'fitting issues' -- the covers are very generic, and don't seem to line up correctly. The other small detail is that there aren't many PSUs with OEM interior lighting!

So, if you want a PSU window, some lighting, and maybe an additional voltage mod, what are the options? Only one really, and that's do it yourself! The supplies that you'll need will be something along these lines:
* A PSU -- the example used is a 250W AOpen 'cheapie',
* cutting tools -- a Dremel, jigsaw or similar, as well as files, sandpaper, etc.
* Perspex (acrylic) off cuts, and five-minute epoxy glue, 
* an 80mm 'tailed' LED fan (PC Range, 08-83229544, $15.00),
* a 100mm cold cathode tube (Jaycar SL-286X, $11.95, Jaycar SL-2868 inverter $9.95),
* green and brown hook-up wire, soldering equipment and heat shrink, and
* a female Molex plug (Jaycar PS-0740, $2.25).

The window.
Fitting a window into a PSU is basically the same as fitting a case window, but a lot fiddlier! The preparation is important – unplug the PSU and take it out of the computer.

Remove the screws that secure the cover. Have a good look for anything that is going to get in the way of fitting the perspex to the inside of the cover, including any of the metal tabs that keep the cover in place. That done, determine the size and shape of the window, allowing at least 15mm 'overlap' around the outside border where the Perspex will be glued in. Once the dimensions are transferred onto the outside of the cover, it is a simple cutting job to remove the excess metal, and then smooth all of the edges with a file and sandpaper. Cut the perspex to size, leaving the protective paper in place except for where the glue will be applied. Make sure to 'rough up' the painted finish on the inside of the cover, and the Perspex, where the glue will go, so that it can 'grab' the surface.

Apply the epoxy resin to the cover, carefully place the window in position and put something heavy on top of the perspex to hold it down firmly while the glue does its thing.

For this project I used 4mm thick red Perspex, but added a bit of a twist. Using a router (the power tool, not the network component), I rebated the thickness of the 15mm overlap area by 2mm, so that the Perspex actually protrudes out past the outside of the cover by 1.5mm (the picture should explain). This gives a 'neon edge' to the window, and the visual effect of more light flooding out.

ABOVE: Chuck your standard fan and replace it with this 7V fan mod.

Lighting and 7-Volt Mod.
There is a simple way to add interior lighting to a PSU -- replace the standard fan (or fans) with an LED fan, which are now available almost everywhere. The project PSU had a three-pin fan connector on the circuit board, so installing the LED fan was a matter of cutting away the 'pressed' fan grill, screwing the fan into position and plugging it in.

I wanted enough light to make the PSU glow like a nuclear reactor meltdown, and not just a mild glow. The solution was to add in a 100mm cold cathode. There was plenty of room for the inverter to be fitted on the inside top of the PSU cover, and the tube fitted across the bottom edge of the window perfectly. Powering the cathode was easy -- solder the wires to the 12V rail on the inside of the PSU, which also kept everything self-contained.

While the soldering iron was still hot, I had another small modding idea -- by using the PCB +12V and +5V power headers as positive and negative respectively, I made up a specialized 7V lead. To save confusion later, I used 'unusual' colour-coding for the lead (green for +Ve and brown for the –Ve), and ran the lead into a normal Molex plug, also labelled as '7V only'.

So, for less than $50 and a few hours work, the AOpen PSU has been converted into something a lot different than the grey box it once was. A worthwhile mod? That's your call!