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One thumbscrew

The 120 mm PCIe fan mount takes a single expansion-slot position and goes in with the case thumbscrew. What that means for your case, and what it does not.

The biggest fan in the collection uses the fewest slots. That is the appeal of the 120 mm mount, and also the one thing worth measuring before you order.

At a glance

120 mmOne fan120 × 120 × 25 mm · not included
1Expansion-slot positiona mounting position, not one slot of space
1Thumbscrewthe one from the slot cover it replaces
The off-white 120 mm PCIe fan mount with a black fan and illustrative airflow
With a fan fitted. The airflow in the preview is illustrative.

Four things to know

  1. One position is not one slot of space

    The bracket uses a single expansion-slot mounting position, but the fan it carries is far larger than one slot. Measure the fan’s thickness and the clearance for the whole assembly beneath the graphics card and around nearby cards and cables, and compare them with the listing dimensions.

  2. It works either way round

    Decide whether the fan should blow toward the graphics card above it or pull air away from it. Most people exhaust warm air from behind the card. Which way should the air go? helps you choose.

  3. The cable has its own path

    Run the fan cable along the frame’s built-in channels so it stays out of the blades, then check the fan turns freely before you power on.

  4. We have no test result for this size

    Our documented results are for a 2 × 40 mm configuration (1.5°C lower GPU temperature) and a 1 × 60 mm configuration (3°C lower). They do not establish a result for the 120 mm mount, so we do not quote one.

Fitting it

Fix a 120 × 120 × 25 mm fan to the frame through its four corner holes with the screws that came with the fan. With the PC shut down and unplugged, remove one slot cover below the graphics card and keep its thumbscrew.

The mount moving into the free slot, with the thumbscrew at its tab
Slide it in like an expansion card; the case thumbscrew holds it · drawn from the real parts, not to scale.

Slide the bracket into the free slot like an expansion card and secure it with that thumbscrew. No tools needed. Connect the fan to a fan header or hub, check it clears the graphics card, then power on. All six steps, drawn, are in the setup guide.

Watch the blades turn and the air move.

See the 120 mm mount

Keep reading

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Compare mounting footprints, read our recorded cooling results, and see what the test does—and does not—establish.

A fan mount moving into free slots below a graphics card
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The two-minute fit check

A tickable checklist for every design. Grab a ruler, open the case, and work down the list before you order.

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The whole collection in one scroll

Twenty-seven designs: four corners of a setup and eight made to order. A quick map of everything in [creations], from the case to the keyring.