Quick Answer

Most FPS drops on a 240Hz monitor setup come from refresh-rate mismatch, VRR state, cable bandwidth or a larger pixel load, not from a broken game. Prove it with RTSS, the monitor OSD and Windows Display settings; 60Hz is 16.7 ms, 144Hz is 6.94 ms and 240Hz is 4.17 ms.

Find The Real Limit

Use one repeatable test scene and record average FPS, 1% lows and frame time. For 240Hz monitor setup, the useful tools are RTSS, the monitor OSD and Windows Display settings. Do not judge by feel alone: 60 fps equals 16.7 ms, 144 fps equals 6.94 ms, and 240 fps equals 4.17 ms.

Checks For This Setup

For 240Hz monitor setup, start here: set the correct refresh rate, enable VRR, use DisplayPort bandwidth, cap FPS 3 fps below refresh, and compare fullscreen with borderless. Keep 240Hz monitor in mind because its driver, firmware or control software can change how the system behaves after an upgrade. Use broad price context as a sanity check: gaming monitors range from about R3,000 to well above R20,000.

If the setup uses online play, separate network stutter from frame pacing. RTSS shows the frame-time graph; ping and jitter tools show the connection. A router change can affect online movement, but it should not reduce local benchmark FPS unless software or USB services changed too.

Settings To Verify

Confirm monitor refresh rate, in-game FPS cap, VRR or FreeSync/G-Sync state, and overlay recording. On GPU builds, check ReBAR, PCIe link width and driver state. On laptops or handhelds, match charger, TDP profile and performance mode to the FPS target.

FAQ

Why did my 240Hz monitor setup start showing FPS drops?

The likely cause is refresh-rate mismatch, VRR state, cable bandwidth or a larger pixel load. Use RTSS, the monitor OSD and Windows Display settings so you can see whether the limit is GPU load, CPU scheduling, storage, USB, audio, thermals or network jitter.

Should I replace hardware first?

No. Many fixes cost R0 because they come from drivers, firmware, FPS caps, refresh settings or power profiles. Buy hardware only after the same test proves the part cannot meet target.

What number proves the fix worked?

Watch 1% lows and frame time, not only average FPS. A good fix makes the graph flatter: 144Hz should sit near 6.94 ms and a 60 fps cap near 16.7 ms.

TIP

Troubleshooting Check

Save one before-and-after result from RTSS or CapFrameX, then keep the setting that improves 1% lows without reducing image quality more than needed.