Monthly Archives: May 2018

PC-In-A-Bag – DIY computing to go –Part 1

Are you sometimes frustrated with the lack of computing power in mobile devices? I Built a device that looks somewhat like a large tablet, but has the computing power of a fully crown PC – no wonder, because it is: The pc itself is hiding under the table. It is permanently built into a leather messenger bag that also has room for the tablet, which is in fact a portable monitor.

A Mini-ITX motherboard, a graphics card and a power supply unit are permanently installed in the bag. A portable touch screen monitor with Full HD resolution is attached via a cable. It also fits in the bag, just like the small Bluetooth keyboard with trackpad and a mouse.

Unlike a laptop, I don’t have a battery in my bag – not yet – but the computer also runs on the cigarette lighter in the car. And at home I can also connect a large monitor and even use both monitors together.

By the way, the pocket computer is very quiet, because it needs only two fans. The processor fan and the graphics card suck in the air directly from outside, which is then released upwards and through the power supply unit.

I’ve been looking for a suitable bag for a long time. I finally bought this one on ebay. These parts are to be installed: A Mini-ITX motherboard with Intel Core I5 6500 processor and a very quiet and flat fan from Noctua as well as 16 GB Ram. An MSI Radeon RX 560 Aero graphics card with 4GB video RAM. Because the two parts are to be mounted next to each other, I need a PCIE riser cable of 20cm length.

Also a 12V power supply, which here has 350 watts, and an M2-ATX power supply, which generates all the voltages that the components need from an input voltage of 6 to 24V. I exchanged it afterwards, by the way, but more about that later.

I had a piece of plywood cut to the inside dimensions of the bag at the DIY store.
Now the components have to be puzzled. And don’t forget that the cables also need space. That’s how it fits.We also need a harddisk. I chose an SSD. In principle, this would still fit next to the power supply unit. Only the cables will stick out too far.

But the plastic housing is only there to give the SSD the dimensions of a 2.5″ hard disk. So I muster the courage to crack the case open. That is actually quite simple, and the actual SSD is not even half the size. Now it has plenty of room. To mount and protect the it, I designed and printed a case that the SSD snaps into and which I can then screw onto the base plate.

I also printed a bunch of brackets.

First I provisionally put the screws through the motherboard to determine the position of the brackets. I then marked them with a pencil. I mixed two-component glue and glued on the parts. For the graphics card I have printed parts that the circuit board snaps onto. These is also glued on. Because the parts kept moving around, I additionally fixed them with hot glue.

Then I marked and drilled the holes. On the back I enlarge the holes with a larger drill bit to countersink the screw heads, because I want to keep a smooth surface. Then the various parts are screwed onto the base plate. The screws are very deep in the whole parts. So I put three nuts in the nut and put the plate on its side to get the nuts on the screws.

I plug in the various cables. I would have been better installed the IO-aperture right away, now that the motherboard is screwed in place, it is a bit complicated.

That’s it for now, the build will be continued next week.