Does a sagging arm always need more tension?

No. The display may exceed the arm’s supported load/depth, the VESA plate may be loose, or the desk clamp/surface may be moving. Verify those before adding tension.

Can monitor depth reduce an arm’s effective capacity?

Yes on some arms. Ergotron explicitly notes depth-related capacity reductions for certain LX models.

Should I tighten the arm as far as it goes?

No. Follow the manufacturer’s adjustment range. If the arm cannot hold a supported display within its normal adjustment range, investigate the load, assembly, or worn hardware.

Monitor arm sagging: capacity, tension, VESA, and clamp checks

A sagging display is not automatically a tension-screw problem. The arm may be outside its supported weight/depth range, the VESA plate may be loose, the desk attachment may be slipping, or the lift/tilt mechanism may simply need model-specific adjustment.

The five-minute answer

Identify the exact arm model. Verify the monitor weight, depth, VESA pattern, and any attached accessories against that model’s specification. Inspect the VESA screws, arm joints, desk clamp/grommet, and desktop for movement or damage. If the load is supported and the mount is secure, follow the manufacturer manual to adjust the correct lift or tilt tension point.

Step 01

Check the exact model’s load envelope.

Do not apply a capacity from one arm to another. Even within Ergotron’s LX family, capacities vary by model, and Ergotron notes that monitor depth can reduce capacity on some versions. Match the model number to the current product sheet/manual.

Step 02

Find where the movement actually occurs.

Screen tilts downward

Inspect the tilt joint and VESA plate before adjusting tilt tension.

Whole arm lowers

Inspect the lift mechanism and verify the display is within its supported load range.

Base moves on the desk

Stop adjusting arm tension. Check the clamp/grommet, desktop material, thickness, and damage.

Step 03

Inspect VESA hardware and the desk attachment.

Power down the display if you need to support or remove it. Check that the correct VESA screws/spacers are seated and that the monitor plate is fully engaged. Check the desk clamp or grommet for slip. If the desktop is cracking, crushing, bowing, or delaminating, remove the load and address the mounting surface before reuse.

Step 04

Adjust only the documented tension point.

Arm designs use different fasteners and directions. Follow the exact manual. Support the display while adjusting, make small changes, and test throughout the arm’s travel. Do not use maximum torque as a substitute for a capacity mismatch.

Decision

Do you need a new arm?

If the supported arm holds position after correct tension and hardware adjustment, keep it.

Maybe

If the display is within weight but unusually deep, curved, or accessorized, check whether the manufacturer derates capacity for that geometry.

Yes

If the display falls outside the model’s supported load/mount range or the arm cannot hold a supported load after correct assembly, choose a properly rated arm or seek service.

Sources

Monitor arm sagging: check capacity and mounting before adding tension.

Check the exact model’s load envelope.

Find where the movement actually occurs.

Inspect VESA hardware and the desk attachment.

Adjust only the documented tension point.

Do you need a new arm?

Allow Pinterest measurement?

Monitor arm sagging: check capacity and mounting before adding tension.

Check the exact model’s load envelope.

Find where the movement actually occurs.

Inspect VESA hardware and the desk attachment.

Adjust only the documented tension point.

Do you need a new arm?

Get the next practical setup fix.