If my 240Hz monitor is only showing 120Hz describes your problem, first check whether 240Hz is missing from the available modes or simply not selected. A PC connection may be limited by its input, resolution, accessory path, or settings; a compatible console may correctly stop at 120Hz. Use the steps below to identify the actual restriction, apply a supported configuration, and confirm that the display stays reliable after reconnecting or restarting.
- My 240Hz monitor only showing 120Hz: Start with the source
- Find out what the number 120 actually measures
- If you use a console, verify 120Hz rather than chasing 240Hz
- Check the monitor’s exact 240Hz requirements
- Select the intended mode in Windows
- Simplify the connection before buying a replacement cable
- Compare one screen and a simpler signal
- Inspect monitor menus and graphics controls
- My 240Hz monitor is only showing 120Hz after an update
- If Windows uses 240Hz but a game stays near 120
- Use the result of each comparison to choose the next step
- Verify the fix and stop if the configuration is unsupported
- Frequently asked questions
- Find the limiting condition before changing hardware
My 240Hz monitor only showing 120Hz: Start with the source
A 240Hz specification describes a capability of the monitor under particular conditions. It does not establish that every connected device, input, resolution, or accessory can deliver that mode.
Start with the source. If you use a PS5 or Xbox Series X|S, a supported 120Hz gaming mode can be the correct result. Those consoles do not become 240Hz sources when attached to a faster monitor.
On a PC, check the active Windows mode, the monitor’s input-specific timing table, and the complete path between the graphics output and display. If 240Hz previously worked, identify what changed before assuming the hardware needs replacement.
| Observation | First thing to investigate | What not to assume |
|---|---|---|
| Console outputs 120Hz | Console and game support | That the monitor should force 240Hz |
| Windows lists 240Hz but uses 120Hz | Selected refresh rate | That a new cable is immediately necessary |
| Windows lists no rate above 120Hz | Supported input mode and connection | That the panel itself is limited to 120Hz |
| Monitor counter varies around 120 during gameplay | Adaptive sync and game frame delivery | That the configured maximum disappeared |
| 240Hz appears only at a lower resolution | Resolution-specific support and bandwidth | That all resolutions share the headline maximum |
The PC instructions here assume Windows 11 and an external monitor. The objective is the monitor’s documented mode, not an unsupported custom overclock.
Find out what the number 120 actually measures
Read Windows and the monitor’s signal information
Open Settings, System, Display, then Advanced display. Select the intended screen and note the resolution, selected refresh rate, and available rates. Check the monitor’s input-information menu too, if it has one.
If both identify a fixed 120Hz signal, investigate why 240Hz is unavailable or unselected. If Windows is configured for 240Hz while the monitor displays a changing refresh counter, consult the manual to determine whether that counter reflects adaptive-sync operation.
A number observed during one game is not enough to identify the connection’s maximum. Make the desktop configuration your starting reference, then compare what changes when the game launches.
Separate FPS from refresh rate
A game overlay showing 120 fps does not necessarily mean the monitor is receiving a fixed 120Hz signal. Frame rate describes how often the game produces frames; refresh rate describes the display’s updates.
A frame cap, synchronization setting, or rendering limitation can hold a game near 120 fps even with 240Hz selected. Conversely, selecting 240Hz does not make a demanding game render 240 fps.
The time per refresh is approximately 8.33 milliseconds at 120Hz and 4.17 milliseconds at 240Hz, calculated as 1,000 divided by refresh rate. Those values are not measured total input latency or promises of doubled gaming performance.
If you use a console, verify 120Hz rather than chasing 240Hz
PS5 supports 120Hz video output for compatible displays and games. Sony provides the setting under Settings, Screen and Video, Video Output, then 120 Hz Output. Its output-information screen helps confirm the connected device’s capabilities.
Xbox Series X|S likewise supports gaming at up to 120 fps with supported content. A 240Hz monitor can still be useful as a shared PC-and-console display, but its higher ceiling does not change the console’s supported output modes.
Not every game uses a 120Hz performance mode, and the monitor must support the console’s requested resolution and timing through its HDMI input. Check those details if the console falls below its expected supported mode.
For this branch, a stable compatible 120Hz result is not a monitor defect. Stop trying PC driver fixes or custom timings on the assumption that the console must output 240Hz.
Check the monitor’s exact 240Hz requirements
Match resolution, input, and model suffix
Find the complete model number on the unit, including any suffix. Open its official manual and locate the supported timing table for the input in use.
Look for the intended pixel resolution at 240Hz. A lower-resolution 240Hz mode does not prove that the display offers 240Hz at every resolution it can accept. Check whether the advertised maximum is native, a manufacturer-provided overclock, or part of a separate display mode.
Input differences are real. Dell documents the Alienware AW2723DF with a default DisplayPort range reaching 240Hz and an HDMI range reaching 144Hz. That example does not explain an exact 120Hz ceiling on an unidentified monitor; it demonstrates why the correct input matters.
Do not use another monitor’s timing table because the brand or screen size matches. The exact implementation determines which modes are supported.
Include compression and image settings where required
Some high-resolution, high-refresh modes depend on Display Stream Compression, or DSC, to fit through the available link. The source, display, and connection configuration must support the required arrangement.
Check the manual for a DSC option, input-version requirement, or compatibility note. Do not disable DSC as a universal gaming optimization: doing so can remove modes that rely on it. Equally, enabling a setting cannot add DSC support to hardware that lacks it.
LG’s high-refresh guidance illustrates a 2560 × 1440 mode near 240Hz alongside input and compression notes, while explicitly directing users to their own model’s supported modes. Treat examples as model-dependent, not universal instructions for every 240Hz screen.
Select the intended mode in Windows
- Right-click the desktop and choose Display settings.
- Use Identify to confirm which numbered screen is the 240Hz monitor.
- Check its desktop resolution against the supported mode you want.
- Open Advanced display and select that same screen.
- Expand Choose a refresh rate.
- Select 240Hz if the documented mode is available.
- Confirm only when the picture returns correctly, then verify resolution again.
Microsoft notes that refresh options marked with an asterisk change the resolution. Selecting one can reveal that a higher rate is available, but it may not preserve your intended pixel dimensions.
If the picture becomes unusable, do not confirm it. Allow the Windows confirmation timeout to restore the previous configuration. A lower rate that remains selected after a restart deserves further investigation, but a one-time unselected 240Hz option may need no hardware fix.
Where Advanced display shows separate desktop and active signal modes, note both. If they differ, inspect the graphics output configuration rather than assuming the desktop resolution alone describes the transmitted signal.
Simplify the connection before buying a replacement cable
Connect directly to a suitable graphics output
Temporarily bypass docks, hubs, adapters, KVM switches, receivers, and capture-device passthroughs when possible. Connect one monitor directly through an output documented for the desired mode.
On a desktop, identify whether the cable uses the intended graphics card or a motherboard output. On a laptop, check the capabilities of the specific HDMI, DisplayPort, or USB-C connection. A fast rendering GPU does not guarantee equal capabilities on every external connector.
If 240Hz appears through the direct route at the same resolution and format, investigate the bypassed path next. The result implicates something changed by the comparison, including cables and accessory configuration; it does not prove that the dock is defective.
A “4K” accessory label is insufficient. Look for the exact resolution, refresh rate, host requirements, and number of supported displays.
Test the cable without changing everything else
Reseat the connection and compare with a suitable known-good cable on the same ports. Use the monitor’s supplied cable when it is intended for the tested mode.
A cable marketed for “240Hz” still needs a resolution and signal format attached to that claim. What works for one mode may not carry a higher-bandwidth combination reliably.
If a replacement also changes HDMI to DisplayPort, record that as a connection-path comparison rather than proof of a faulty cable. Establish the documented requirements before spending money on an upgrade.
USB-C adds another check: the host port and accessory must provide the appropriate video transport. A charging-capable connector alone does not establish high-refresh display support.
Compare one screen and a simpler signal
Remove mirroring and shared display loads
Press Windows + P and choose Extend, or the appropriate single-screen option, for the initial test. Duplicate mode can restrict the available shared configuration.
Disconnect secondary monitors temporarily, especially if they share a dock or DisplayPort multi-stream link. Intel notes that multiple streams must fit within the connection’s combined bandwidth.
If 240Hz returns, reconnect displays individually and inspect their settings. A secondary 120Hz monitor does not universally force an independently configured gaming screen to 120Hz. Investigate the particular shared connection and projection mode instead.
Keep the main screen’s resolution unchanged during the comparison. Otherwise, the test may accidentally combine several reasons for the higher rate becoming available.
Check whether HDR or color depth changes the available mode
Resolution, refresh rate, and color depth affect the amount of video data the connection carries. If the monitor’s documentation supports feature-dependent combinations, temporarily compare standard SDR output or a supported lower-bit-depth configuration.
Change one setting at a time and retain the original values. If 240Hz becomes available, check whether the original combination requires another input, DSC, or a different documented configuration.
Do not assume that HDR always prevents 240Hz. Also avoid accepting reduced-chroma output without checking desktop text quality. The useful goal is your intended resolution, refresh rate, and image quality together.
Inspect monitor menus and graphics controls
Open the monitor’s on-screen display and review the active input, port-version setting, refresh limit, and any documented high-refresh mode. A compatibility setting intended for older devices can change the available configurations.
Follow the exact-model instructions. Some screens expose a refresh-rate selector; others rely on the source selection. Picture-by-picture or other multi-input features may impose restrictions on some models, so disable them for comparison only when the manual identifies relevant limits.
For NVIDIA-controlled displays, open NVIDIA Control Panel, choose Display, then Change resolution, select the monitor, and inspect its existing modes. If the resolution list has multiple groups, check the appropriate supported PC-resolution entry.
For AMD and Intel systems, use Windows Advanced display first, then inspect current vendor software where relevant. Hybrid laptops may route the output through integrated graphics even when a discrete GPU renders the game.
Restart the PC and power-cycle the monitor according to its instructions after appropriate setting changes. Note customized preferences before attempting a monitor reset.
My 240Hz monitor is only showing 120Hz after an update
A previously working configuration calls for comparing changes. Record the last working ports, cable, resolution, image format, and driver version, then inspect what the update altered.
Open Device Manager and expand Display adapters. If the relevant device uses Microsoft Basic Display Adapter, Windows is using its generic graphics driver. Microsoft recommends installing an appropriate manufacturer-specific driver for the hardware.
Use Windows Update, the PC manufacturer’s support resources, or the graphics vendor’s official driver page. Review OEM guidance for laptops rather than updating only the GPU whose brand you recognize.
If the restriction began immediately after a graphics-driver update on an otherwise unchanged setup, Microsoft documents rollback through the adapter’s Properties, Driver, and Roll Back Driver. The option requires a retained previous version.
If a supported reinstall is necessary, save work and obtain the correct package and instructions before removing the existing driver. Restart and repeat the same test afterward. Avoid unrelated BIOS updates, registry changes, or driver-cleaning utilities as an automatic response to this symptom.
If Windows uses 240Hz but a game stays near 120
Check the game’s selected display and any resolution-and-refresh selector. Compare its supported full-screen and borderless configurations, because games do not all choose output modes in the same way.
Then inspect the game’s frame cap and any relevant graphics-driver profile. A 120 fps limit can be intentional. Synchronization behavior and actual rendering performance also affect the observed result.
Do not infer a hardware “half refresh” fault solely because 120 is half of 240. That arithmetic does not identify whether the cause is a game limit, output timing, or adaptive-sync behavior.
On supported Windows 11 systems, consider Dynamic Refresh Rate if a game operates below the expected rate. Microsoft notes that DRR can limit some games and recommends disabling it for that specific problem. It is not the explanation for every missing 240Hz option.
Use the result of each comparison to choose the next step
A useful test changes one part of the configuration and produces an observation you can repeat. Interpret the result narrowly rather than replacing several components based on a guess.
| Comparison result | What it supports | What to do next |
|---|---|---|
| Selecting an existing 240Hz option works | The lower rate was a selection issue | Verify stability and keep the supported mode |
| A direct route restores 240Hz | The bypassed path affects availability | Review its accessory, cable, and host requirements |
| A different cable restores 240Hz on identical ports | Cable condition or seating was involved | Repeat the test before replacing other hardware |
| SDR works but the original signal format does not | The feature combination matters | Check bandwidth, compression, and exact supported combinations |
| A previous driver restores the same mode | The driver comparison implicates a regression | Record versions and report the reproducible difference |
If another computer is used for comparison, verify that its output supports the intended resolution and rate. A second source that is also limited to 120Hz cannot establish that the monitor is faulty. Keep the original input and cable unchanged when they are the parts you want to compare.
Verify the fix and stop if the configuration is unsupported
Confirm the selected Windows rate and the monitor’s input information at your intended resolution. A nominal 240Hz mode may appear as a nearby fractional value; LG’s illustrative timing table includes 239.97Hz.
Test desktop use, a familiar game, restart, and sleep and wake. Reconnect accessories and restore features individually, checking whether the 120Hz restriction returns. Note any new blackouts, flicker, or artifacts.
If another compatible computer can drive the monitor at 240Hz, investigate the original source and connection. If multiple verified compatible sources fail on the supported input, contact the monitor manufacturer with the exact models, driver versions, and comparison results.
Do not force a custom 240Hz timing to bypass an unexplained limit. An accepted entry cannot upgrade a source, input, or converter. Use a stable supported 120Hz mode while investigating when necessary.
For persistent Windows output problems, its recovery startup settings include Enable low-resolution video, which lets you reset display settings. Have the BitLocker recovery key available on encrypted devices. Undo monitor-menu changes separately according to the manual.
Frequently asked questions
Does every HDMI connection support 240Hz?
No. Support depends on the source, monitor input, resolution, signal format, and connection. Nor is HDMI universally limited to 120Hz. Check the exact supported mode at both ends.
Do you need 240 fps to select 240Hz?
No. A supported desktop output mode can be selected independently of a particular game’s performance. Higher game frame delivery can make more use of the display, but low FPS does not itself explain an absent Windows option.
Will turning off G-SYNC or FreeSync unlock 240Hz?
Only investigate that if the manual documents a restriction or a controlled comparison identifies an interaction. A changing adaptive-sync counter is not equivalent to losing the configured 240Hz maximum.
Is 120Hz normal on a PS5 connected to a 240Hz monitor?
Yes, for compatible high-refresh games and output modes. The monitor’s higher capability does not turn PS5 into a 240Hz source. Verify the supported 120Hz configuration rather than seeking a nonexistent console 240Hz setting.
Find the limiting condition before changing hardware
Identify the source and what the 120 reading measures. On a PC, match the exact 240Hz resolution and input requirements, select the mode, and isolate accessories, feature settings, and driver changes in order.
Keep a record of the working combination. A reliable supported result is the goal, whether that means restoring 240Hz on a compatible PC or confirming that 120Hz is correct for the connected console.
