How to Adjust Computer Monitor Arms? | Match Tension To Your Screen

New monitor arms cause the same confusion every time. The screen drifts downward, or pops upward on its own. Both problems trace back to one thing: the arm’s counterbalance spring or gas cylinder isn’t matched to your monitor’s weight. Fixing it is simple once you know the pattern — attach the monitor, then tune a few screws.

Before you start, confirm two details. Your monitor’s VESA pattern (the hole spacing on the back) must match the arm’s mount, and the screen’s weight must sit inside the arm’s rated range. Any arm, from gas-spring to fixed, balances wrong without this match.

Set the Tension in the Right Order

Tension adjustment only works correctly while the monitor is fully attached. The spring’s job is to cancel out the screen’s actual weight, so the arm needs that weight present before you tune it. Attach the monitor first — then touch the tension screws.

Raise the arm straight up, as vertical as you can manage, before reaching for the Allen key. Most arms then expose the main tension screw at the top of the pivot. Find the wrench that came with the arm — many use a 6 mm or large M6 Allen key for the top joint, with smaller tools like a 4 mm hex or M3 wrench for the swing and swivel joints.

Turn the screw a half turn at a time, then test the arm’s motion before adjusting further. Expect to make several small passes. The correct setting holds the monitor at your chosen height and moves smoothly when pushed, without drifting on its own.

Which Way to Turn the Tension Screw?

Watch the screen’s behavior and turn accordingly. A monitor that sags or drops needs more lift force; a monitor that rises or floats upward needs less.

• Screen drops: Tighten the screw clockwise toward the “+” marker to increase tension.
• Screen rises on its own: Loosen the screw counter-clockwise toward the “-” marker to reduce lift force.
• Slightly stiff motion: Loosen a touch to let the arm glide more freely.
• Jerky or bouncing movement: Tighten slightly, then loosen a half turn to find the smooth zone.

If the arm has separate swing or swivel joints and one of them drifts, use the smaller hex key for that specific joint and repeat the same opposite-direction pattern. Support the monitor with one hand while tightening any screw, so the mechanism isn’t carrying the full load during adjustment — a good habit that protects both the mount and your fingers.

Positioning the Monitor for Your Posture

Once the arm balances, set the ergonomics. The top edge of the screen should sit at or just below eye level while you sit in neutral posture, with the display roughly an arm’s length away.

For standing desks, check the height in both seated and standing positions before finalizing the arm’s angle and any preset positions. Leave enough slack in the cables so their pull doesn’t disturb the tilt or height you just set.

Many arms settle differently on each side of a dual-monitor setup. Adjust each arm independently if one side sits lower or drifts more than the other.

Monitoring arm check: what to keep an eye on

Two mistakes cause most frustration. Examining the monitor’s weight rating and VESA compatibility before buying avoids awkward surprises at setup. And skipping the “test after every half turn” rhythm sends people chasing their tail — either overtightening until the mechanism feels jerky, or under-tightening until the screen bounces.

Choosing an arm rated for your monitor’s size makes the whole job easier. If you’re still shopping, look at arms with strong weight ranges and solid joint construction—our tested roundup of the best monitor arms covers the options that hold position without fuss.

FAQs

Why does my monitor arm sag after a few weeks?

Do I need to adjust tension on a fixed arm the same way?

Fixed monitor arms work differently than gas-spring models. Instead of a tension screw, you loosen the height bracket clamp, reposition the monitor to the desired height, and re-tighten the bracket firmly. The monitor’s weight is then held by the clamp’s friction rather than by a counterbalance spring.

What size Allen wrench do most monitor arms use?

Common sizes include 6 mm, 4 mm, M6, and M3 Allen keys, depending on the model and which joint you’re adjusting. The main tension screw typically uses the larger wrench, while swing and swivel joints use a smaller hex key. Check the manual or the tool set that shipped with your specific arm.