BC250 / BC-250 Full-Size ATX PSU Case

A case for a BC250 board and a full-size ATX PSU.

Note - the main image uses an optional fan grille fron Noctua, this is separate from my design but recommended to protect your fans. Link: https://www.printables.com/model/1096961-high-efficiency-noctua-120mm-fan-grill

Features

• Mounting holes for 2 Arctic P12 Pro fans (1 side, 1 front)

• Fan configuration is "push" on an open-fin BC250 heatsink on the side, and "pull" out the heat using the front fan

• Room for ATX PSU cabling if you don't have a modular supply

• Mounting rail to slide the BC250 in

• Mounting rail has 2 holes for cable management and 2 cable tie slits

• Push-fit plug to screw the BC250's IO shield to and secure it

• Plenty of room for a heatsink on the BC250 backplane between it and the PSU

• Gap for IO shield and 1 180 degree angle USB jack to allow mounting an internal drive

• Front hole for a 22mm diameter switch

• Dimensions: w200mm, h200m, d340mm

• An optional internal "basket" for holding PSU cables if you don't have a modular PSU

AI Disclaimer - The case design is my own. I used AI tools to help me build the design in a 3d modelling tool.

Temperatures

• The BC250 is a lottery temperature-wise depending on the board you have

• I run mine at 40cu, 1500 MHz and temperatures hover around 60c

• A Furmark benchmark of 40cu, 2000Mhz was hitting low to mid 80c

Printing

• Designed for PETG, do not use PLA due to the BC250 temperatures

• All pieces can print on a single 1kg roll (tweak your slicer settings if you are going over this)

• 2 main case pieces, can take 12 hours per case half depending on your printer

• Fits a 220x220x230 print bed

• You will only need supports for the screw bore holes and the BC250 mounting rail where they meet the print bed - this should result in very minimal supports. You won't need supports for the vent design. You might be able to avoid any supports if your printer is good at bridging

• A brim will help if you have issues with warping. You can use a de-burring tool to remove the brim afterwards

Note that my PSU is an EVGA 600W and the spacing of the power socket and switch may be different to yours - a single layer test print of the rear of the case is strongly recommended for a fitment check!

I will adjust the model for a more universal fit if needed.

Hardware

• Fan splitter so you can wire 2 fans to the BC250 fan header

• 8 fan screws

• 1 M3 5mm/6mm screw to secure the board to the rear plug

• 11 M3 countersunk (5mm or 6mm length is plenty) screws for the central join (optional)

• The central join is optional to screw in place - mine is secure enough with the side-fan screwed in as it also joins both sides of the case

• PSU screws

• A 22mm diameter switch for power

Assembly

• Print each side. Rear first is recommended as you can have an operational system while you wait for the front

• Print the rear plug

• It is recommended to print 2 grilles for the fan to help protect the blades from fingers and internal wiring: https://www.printables.com/model/1096961-high-efficiency-noctua-120mm-fan-grill

• Secure the PSU to the rear of the case, fan to the external side

• Screw the side fan in to the rear of the case, you'll only be able to screw 2 holes in until the front is ready. Use the optional grille to both protect the outside of the fan and get it closer to the BC250. The fan should be "blades out"

• Unscrew and remove the metal plate n the BC250 that's the opposite end to the IO shield

• Slide the BC250 in so the heatsink fins are against the side fan

• The BC250 is designed to fit vertically in the case. This is to allow the weight to be distributed on the inner rails, and to give the PSU and P12 fans air to breathe at the sides

• Plug in the rear case plug to the hole to the side of the IO shield cutout and screw the IO shield to it with the M3 screw

• Wire your PSU and fan to the BC250 and check things are working

• When the front is printed, screw the second fan to the inside front. The blades should be on the inside of the case, not the case wall. Screw the second fan grille over the top to protect it from internal wiring

• Wire this fan to the BC250 using a fan splitter

• Secure the power switch to the hole

• Use the optional cable basket to hold your non-modular PSU cables in place if needed. This can be pushed up against the PSU and should be held in place by the cable weight

• Slide the front of the case onto the rear

• Screw the other side of the side fan in place

• Screw 11 M3 countersunk screws in the join holes if you feel it needs it

History

• Added front/rear v2 versions with a less-deep chamfer. This is to fix an issue where the front half of the case join culd split at the joint corners. If the case is screwed together this is a cosmetic issue