Mini Tower Case for Dell Optiplex 7040 SFF Motherboard

Off-lease business computers are one of the best ways to get decent (if slightly older) hardware for cheap.  I grabbed a optiplex 7040 with a i5 6500, 16gb RAM and a 512GB SSD for less than $150.  The down side is that the OEM PSU isn't sufficient to power a proper GPU, and the case isn't big enough to fit one anyway (or a real PSU for that matter).  In their infinite wisdom, Dell makes their motherboards in a weird size and shape so you can't just chuck it in a normal micro ATX case.  I wasn't going to let my old RX480 continue collecting dust, so I designed this fully printable tower case to accommodate it and the requisite ATX power supply.  The case will fit a dual-slot GPU up to 275mm (10.8") long.

I tried to give the case as much airflow as possible, but PCs still get pretty warm.  PLA is not recommended.  I printed mine in ABS.  Print all parts as provided.  The only ones that need support are panel O and the optional hard drive cage.  Normal supports on build plate only are fine.  

Assemble panels as per the included diagram.  Assemble A, B, C, and D into the bottom panel, E and F into one side, G and H into the other side, I and J into the front, and O and P into the back.  Attach the front and sides to the bottom and each other, then attach the back.  Attach K, L, M, and N to each other to make the top cover.

For the power switch, you'll need to either hack up the original connector or just solder ome wires directly to the pins.  Wire it up as per the pinout diagram.  Attach with 8mm M3 bolts

Parts needed:

ATX to optiplex adapter cable (or just splice into the factory connector) https://www.amazon.com/gp/product/B06XGWRTHC

6mm tactile bushbutton https://www.amazon.com/Momentary-Tactile-Through-Breadboard-Friendly/dp/B07WF76VHT

120mm case fan with 4 pin connector

A shit-ton of M3 hardware.  I didn't count exactly how many nuts and bolts, but it's a whole bunch.  You'll want 8mm for the blind holes and 20mm for the through-holes with nuts. Also a handful of very short bolts and two 30-40mm bolts.  Use standard PC case screws to attach the MB and PSU to the case.