Setting up an adjustable monitor stand takes about 25 minutes: align your monitor’s 75mm or 100mm VESA pattern with the arm, secure the plate with four M4 bolts, attach it to the arm, clamp the base to your desk, then adjust spring tension with the included Allen wrenches.
A monitor arm that sags or drifts isn’t broken — it’s unadjusted. Most adjustable monitor stands ship with the spring tension set for a middle-weight display, so a lightweight screen pops upward while a heavy one sinks. One 15-minute session with the included wrenches fixes both, and the steps are the same whether you bought a budget single arm or a heavy-duty dual mount. Here’s the exact procedure, bolt sizes, and tension tricks that make a new stand feel dialed in.
Before You Start: What You Actually Need
Every adjustable monitor stand uses the same core hardware, regardless of brand. Check the back of your monitor for a square pattern of four screw holes — that’s the VESA pattern. Most are 100mm x 100mm; smaller monitors sometimes use 75mm x 75mm. The arm’s VESA plate has slots for both.
You’ll need the M4 bolts that came with the stand (usually four M4x12mm), a Phillips-head screwdriver, a flat surface on your desk for the clamp, and the two Allen wrenches packed with the arm: a long M6 for vertical tension and a small M3 for swing and tilt.
Bolt Sizes That Actually Fit
Most monitors have a flat VESA plate that works fine with M4x12mm bolts. But some monitors, especially larger ones, have a recessed mounting surface that’s deeper than 12mm. If your bolts barely catch the threads, swap to M4x16mm or even M4x18mm — the packaging often includes these longer bolts in a separate bag. Using bolts that are too short is the single most common mistake; the plate loosens over hours and the monitor tilts forward.
Step 1: Attach the VESA Plate to the Monitor
Lay the monitor face-down on a soft surface (the foam packing sheet works perfectly). Hold the VESA plate against the back so its four holes line up with the monitor’s threaded inserts. Insert each M4 bolt and tighten with a screwdriver until snug — don’t crank it. The plastic VESA plates on some arms can crack if over-tightened.
If the plate rocks or the bolts don’t seat flush, check for included plastic spacers. Some stands ship with thin washers that need to sit behind the plate to keep it flat against the monitor back. Missing a spacer bends the plate and throws off the entire mount.
Step 2: Mount the VESA Plate to the Arm
The arm has a metal bracket with a center hole. Drop the quarter-inch bolt through the center of the VESA plate, add the black washer and the lock nut, and tighten with a screwdriver or ratchet. This is the joint that carries all the monitor’s weight — make sure it’s fully seated before you hang the display.
Step 3: Clamp the Base to the Desk
Desk clamps work on most flat surfaces. Open the clamp wide enough to fit your desk edge, then turn the knob until the foam pad presses firmly against the underside. A clamp that’s hand-tight will wobble; cinch it with the included handle or a coin until the base doesn’t shift when you tap it. For glass desks, place a thick cloth between the clamp and the surface — the metal edge can score the glass over time.
If your desk has a cable grommet hole, use the grommet mount instead. It’s more stable and keeps the clamp out of your knee space. The process is the same but uses a smaller bracket that feeds through the hole.
The Moment of Truth: Hanging the Monitor
Hold the monitor with both hands and line up the VESA plate with the arm’s slots. Slide it into place — you’ll hear or feel a click as the safety lock engages. Gently release your grip and let the arm take the weight. If the monitor shoots upward or drops immediately, don’t panic; that’s the tension being wrong, and the next step fixes it.
Before you start adjusting, check that our team’s curated picks for the best adjustable monitor stand include tested models that fit a range of weights and desk types — the best adjustable monitor stand roundup covers the top options for single and dual setups.
| Tension Issue | Wrench | Adjustment Direction |
|---|---|---|
| Monitor pops up on its own | M6 (long) | Turn counter-clockwise (–) |
| Monitor slowly sinks down | M6 (long) | Turn clockwise (+) |
| Arm won’t swing left/right | M3 (small) | Loosen, reposition, re-tighten |
| Tilt feels loose or too tight | M3 (small) | Adjust at hinge bolt |
Step 4: Adjust the Spring Tension (The Part Everyone Gets Wrong)
Locate the tension-adjustment bolt on the arm’s main joint. It’s usually on the underside or the back, marked with a plus (+) and minus (–) symbol. Use the long M6 Allen wrench. If the monitor fell after you hung it, turn the bolt clockwise — each full rotation increases the spring pressure. If the monitor shot up, turn counter-clockwise. Make small turns: a quarter-turn at a time, then test by lifting and releasing the arm.
Once the monitor stays put at any height you set it, the vertical tension is correct. Now adjust the swing tension with the small M3 wrench. Loosen the side bolt slightly if the arm won’t swivel freely, or tighten it if the monitor drifts sideways on its own.
Step 5: Level the Screen
Grasp the left and right edges of the monitor frame and tilt gently until the screen is level. On most arms, the tilt hinge holds its position once you release it. If the monitor droops forward, tighten the tilt tension bolt with the M3 wrench until it holds firm. The typical tilt range is -5° to +15°, which covers both standing and seated viewing angles.
What Success Looks Like
When all adjustments are correct, the monitor stays wherever you push it — at eye level, slightly above, or pulled close for detail work. The arm swings left and right with a light push but doesn’t drift. There’s no wobble at the desk clamp, and the cables run cleanly through the arm’s built-in clips.
If the arm still sinks or rises after a full turn of the M6 bolt, check your monitor’s actual weight against the arm’s rated capacity. Spring-tensioned arms typically max out at 13 lbs (4.5 kg). Steel-geared arms like the Full Motion MI-2752 handle heavier loads. Never exceed the rated limit — an overloaded arm can fail suddenly and drop the monitor. Vari’s monitor arm adjustment guide goes into more detail on fine-tuning tension for specific display weights.
| Component | Bolt or Tool | Torque Guidance |
|---|---|---|
| VESA plate to monitor | M4x12mm (or longer for recessed) | Snug, not tight — plastic plates crack |
| VESA plate to arm | 1/4″ bolt + washer + lock nut | Firmly seated, carries all weight |
| Desk clamp knob | Hand-tighten plus coin twist | Base doesn’t shift when tapped |
| Spring tension bolt | M6 Allen wrench | Quarter-turn increments only |
| Swing/tilt bolts | M3 Allen wrench | Loosen slightly, then re-tighten |
The Most Common Problems and Their One-Line Fixes
Monitor won’t stay level after adjustment — the tilt bolt at the hinge might need tightening with the M3 wrench until it resists gravity. Clamp keeps slipping off the desk — the desk edge might be too thin or too thick for the clamp’s range; many arms include adjustable pads for different thicknesses (usually 0.4 to 3.3 inches). Arm won’t reach where you want it — most single arms have a reach of 20 to 30 inches; consider a wall mount if your desk layout puts the clamp too far from your seating position.
FAQs
Are monitor stand VESA plates universal?
Most are. The standard 100x100mm and 75x75mm patterns cover nearly all monitors under 27 inches. Larger and ultrawide monitors sometimes use 200x200mm patterns, which require an adapter plate or a specific arm that lists that pattern in its specs.
What do I do if my monitor arm won’t hold position?
First verify the monitor’s weight is under the arm’s rated capacity, then adjust the spring tension using the M6 wrench. Turning the tension bolt clockwise adds lift — one full turn usually corrects a sagging monitor. If it still drifts, the gas spring may have failed and the arm needs replacement.
Can a monitor arm damage my desk?
It can if the clamp has no protective pad. Most arms include a foam ring that sits between the metal clamp and the desk surface. Without it, the clamp can scratch wood or crack glass. Put a thick microfiber cloth under the clamp as insurance.
How much weight can a typical monitor arm hold?
Entry-level spring-tension arms support 6 to 13 pounds. Heavy-duty steel-geared arms hold 20 to 33 pounds. Always check the spec sheet before mounting — an overloaded arm won’t stay in place and can eventually fail, dropping the monitor onto your desk or lap.
Do I need to mount into a wall stud for a wall-mounted stand?
Yes. Drywall alone cannot support a monitor arm’s leverage force. Use a stud finder to locate a wood stud, drill a pilot hole, and use the lag bolts provided with the mount. If you must mount on concrete or brick, use appropriate expansion anchors rated for the total weight.
References & Sources
- Vari. “Monitor Arm Adjustment Instructions.” Official guide on M6 spring tension and M3 swing tension tuning for Variable monitor arms.