120mm PCI slot fan duct

thingiverse

This is a simple fan mount/duct that takes up approx 3 PCI slots and provides a duct for a 120mm fan. Attach the fan thru the holes using zip-ties. Note that it may impede on the 4th PCI slot some, but it will fit okay if it's something that isn't too big. Mine co-exists with a serial-backplate in the next PCI slot. This part has support built in which I think should be sufficient on most printers. It should be printed with the large, flat "bottom" facing down as shown with the purple render on the printing grid in my picture. Depending on fan direction, this can be used as intake or exhaust. I like to use it for intake and put a piece of filter over the back, so the fresh air is drawn in at the front (HD bay) and and back (PCI slot duct) which helps cool the expansion cards and such. Dropped video card temps considerably having fresh air come in so close to the GPU fan. Then all the hot air is exhausted out the CPU and PSU fans at the top of the case.