For those intrepid people who wish to mod the cover of the psu I will show you a few ways to do that. I only recommend this to people who are comfortable working around electricity. I will show you how to do this safely but even with a psu unplugged it contains enough voltage to at least give you a good shock, and possibly significantly shorten your life. Please, if you are not sure you know what you are doing, ask for help or don't do it at all. I take no responsibility for any mistakes, you have been warned. The following wiring diagrams and information is for all ATX compliant power supplies.
Some manufacturers, Dell among others, use different layouts and wiring. Always make sure you have the layout and wiring diagram for your specific power supply before attempting any wiring changes.
First off make sure that the PSU is switched off, and unplugged from all other connections. Taking the top cover off is a simple matter of finding the small screws that hold it on. Sometimes they are under a sticker so if it does not come off easy look for another screw.
You don't want to take out the screws from the front of the case yet. I circled the screw locations on an Antec 400w psu to give you an idea. DO NOT try and pry it off, poking around a psu with a screwdriver is a bad idea.
Once you have the cover off you want to be careful as to what you touch. On the board you will see two or more large round cylinders, they look like vacuum tubes. These are called capacitors and one of their functions is to store power. They are most likely drained but never assume this. In order to make sure, you will need to short them out. You may have to take the board off to do this. I circled the screw locations on an Antec 400w to give you an idea. There are two pins on the bottom of them, a power and a neutral. You want to use a sufficiently sized resistor and place it across the pins, being careful to hold the resistor only in the middle, not by the metal pins on the side.
The easier way is to use an INSULATED screw driver to short them out; a plastic handle does not guarantee it is insulated. Simply place the screwdriver across the pins, being careful not to touch any metal. After you have done this you should be ok.
If you want to remove the fan then you will first need to disconnect the wiring from the board. For those that have a basic understanding of AC electricity, and are not already aware, a computer psu is using dc, so be aware of your wire colors. In most case there will be four wires going to the fan.
You will have a red and black which are your two power legs, positive and negative respectively, plugged into the board. These are hot whenever the psu is plugged in regardless if it is on or not. The other pair should be a black and white. These plug into the motherboard and are what tells the fan in the power supply to turn on.
When using the fan without it being connected to the board you will need to short the black white wire. I usually cut them real close to the fan, strip them and solder them together and glue them to the back of the fan with a glue gun, making sure they will not touch anything. The red and the black need power and will go to your power source, make sure the voltage is correct. The screws on the front of the power supply that hold the grill in place should come out easy enough, and then you simply have to wiggle the fan loose from the bracket.
With the cover off of the psu you can do any number of things to it. Whatever you do make sure that the original screws holes line up and that you preserve the vents. They get mighty hot and just like anything else they need to be vented, preferably outside of the case. For starters you might want to add some LED's (Light Emitting Diodes) to the PSU. I will talk more about that when we get to lighting.
You could paint the case, or cut a logo in it. Painting is not too challenging if you are not picky and looking for perfection. If this will be a show piece then you will require some tools and a dedicated work area. With practice, anyone can prep and paint a case like the pros. A simple kraylon special paint job will suffice for now though.
You first need to make sure the area to be painted is clean of any stickers and residue, I use lacquer thinner to clean and remove stickers. Be careful with this stuff, if you get it in your eyes flush them with plenty of water. It will burn for a while. Never use paint thinner, acetone, nail polish remover, or any sort of graffiti remover, for you will have problems with the paint sticking to the metal. You should not try to sand off any stickers either as this will scratch the glue into the metal. When this is done give it a light sanding for the paint to have some texture to adhere to. 320 grit is fine, and off you go.
For the perfectionist, 2 or 3 layers of paint will cover any scratches made. If for some reason you have a psu with a plastic case use only denatured alcohol, the lacquer thinner will be absorbed into the plastic and may soften it or otherwise damage it. A quick note for those that are not aware, lacquer based and acrylic based spray paint do not mix. The lacquer base is stronger and if applied with acrylic they will peel right up within seconds. You need to use one or the other, or completely strip the surface to be painted if you need to switch for some reason.
Cutting a design requires special tools but with a little planning and patience should not pose a problem to the average person. I will talk more about advanced painting and basic metal work later on. These ideas require only basic household tools and should be able to get you started on your way to a standout custom rig. This is just the tip of the iceberg though, I will be posting new articles as I have the time and pictures. There are many more things that can be done with only simple tools and some Yankee ingenuity. The only limit is your imagination, creativity and patience.
Starting off with small projects is best. Don't jump in over your head right away. Install a few lights or a fan with led's in it. The most important things to remember are to finish what you started. No matter how bad it is turning out, you will learn. Take care to work safely.
For those that want to or need to run 2 or more power supplies there is a trick. Normally a psu must be connected to the motherboard in order for it to run. You can bypass this by shorting out the green wire with any black wire on the 20 pin motherboard connector. The psu will then run normally.
The easiest way to do this is with a paper clip. Dont worry about shocking yourself it is all low voltage. Insert one end of the paper clip into the molex slot connected to the green wire and the other to a black lead. If you don't have a green wire then you want to find the wire label ps_on or you can simply try shorting every wire to black and see what happens. You will know it is on when, if you remembered to short the psu fan, it turns on. Remember this is DC not AC, green is not ground your black is the ground (negative).
For those that are interested and willing to put up with crappy ascii art here is the pinout out used for the standard ATX power supply connectors. I used "Upgrading and Repairing PC's" by Scott Mueller for the following infomation.
Code:--------- orange +3.3v | | | +3.3v orange orange +3.3v | | | -12v blue black gnd | | | gnd black red +5v | | |--- ps_on green black gnd | | | | gnd black red +5v | | | | gnd black black gnd | | |--- gnd black grey pwr_ok | | | -5V white purple +5sb | | | +5v red yellow +12v | | | +5v red --------- #10 #20 ATX 20 pin mobo connector Molex p/n 39-01-2200 #1 ---- black gnd | | black gnd |-| | black gnd | | | orange +3.3v |-| | orange +3.3v | | red +5v | | ---- #6 ATX aux conector Molex p/n 8993 #1 #3 ------- black gnd | | | +12v yellow black gnd | | | +12v yellow ------- #2 #4 ATX 12v power connector Molex p/n 39-01-2040 #1 ---- | \ yellow +12v | | black gnd | | black gnd | | red +5v | | | / ---- #4 Peripheral connector AMP 1-480424-0 #1 ----- red +5v | | black gnd | | black gnd | | yellow +12v | | ----- #4 Floppy connector AMP 171822-4