Originally posted 9/26/2007Okay, so I'm finally all done with everything I wanted to do to my Dotmation game in so far as the power supply and adding some ventilation to the top box.
First, things I learned along the way.
In addition to
AZSlot's directions on what wires to connect to where from an ATX power supply, I discovered as mentioned previously that on my ATX supply, the green wire from the 24-pin connector must be cut and spliced together with a black ground wire from the same connector to make my ATX supply turn on.
I also learned that (at least on the ATX supply I bought) that the solid yellow wires that can be found on the 24-pin connector, as well as on the rectangular 4-pin "hard drive power" connectors are the "+12V1", and the yellow with black stripe wires, only found on the square 2x2 4-pin connector is are the "+12V2". In my case it made a difference, as on the power supply I bought, only the +12V2 was rated with enough amps to drive the Dotmation display. I connected the +12V2 power wire to the Dotmation display, while I successfully used the lower-amperage +12V1 to power the circuit board that drives the display. I'm also using the +12V1 to run some fans, seen below.
I found the diagrams and definitions of the standard ATX power supply connectors on pages 36 through 39 of
this .pdf document to be helpful in telling me what wires were what, and confirming that I was clipping and connecting the correct wires.
From what I've read, heat is the biggest problem with the Dotmation displays. I'm using an ATX power supply and using Velcro, I have mounted it to the back of the dotmation box -- since the supply has its own fan, and it is outside of the metal enclosure of the Dotmation box, I have eliminated one big source of heat in that box.
I bought a three-pack of Velcro-brand "Industrial Strength" strips at Wal-Mart for about $2. I used two of the strips as pictured to mount the power supply. I let the Velcro sit as pictured for 24 hours before mounting the supply to the Dotmation box, as recommended by the Velcro packaging (to provide maximum adhesion of the Velcro to the metal).
Next, I searched eBay and picked up a couple of fans. I bought a small muffin fan which fit perfectly on the vent hole on the right rear of the top box. I unscrewed the metal "grate" plate that was there and put the fan in its place. Conveniently, the holes for the fan fit perfectly over two of the screws that are sticking out of the cabinet (originally designed to hold that metal grate in place. I trimmed a small triangle of Velcro and added that to the top corner that wasn't being held by the screw post, and used that to hold that side in place.
I put the grate on the other two screw posts that were still exposed, just so I wouldn't lose it should I decide to put it back in its proper place at a later time. I spliced the wiring into a spare set of wires from the ATX supply, and now I have great air flow blowing out of the cabinet. Roughly $5
including shipping on eBay for the fan.
I noticed that the display itself still gets warm after a while. I picked up another fan on eBay that is designed as a "hard drive cooler":
The size is perfect, and it has the molex connectors to make it plug-and-play. Roughly $4
including shipping.
I had to do some creative bending of the metal (thin, soft metal) to make it fit where I needed it, but once I did that, I drilled a single hole in it to help me use the screw post sticking out of the side of the Dotmation box, and then cut a thin strip of Velcro to help hold in in place as well as using a nut on that screw post.
That fan thing is really thin -- it fits very nicely along the side of the Dotmation box, and there's still plenty of room on the side of it for air to flow out of the box, with the help of those two fans sucking it out into the top box, where that heat then gets sucked out of the main top box with the larger muffin fan.
Here's what it looks like installed (although it's a slightly blurry out-of-focus picture). The arrow points to the fan I just added.
Overkill, probably, but now I'm sure that display isn't going to die of heat -- not on my watch, anyway.
Oh, and not pictured, but I used a couple of plastic cable ties to bundle up all the extra, unused wires coming out of the ATX power supply so it's fairly neat back there behind the Dotmation box.