Every game I play looks like it is running at 60 Hz, even when the FPS counter reports around 400 FPS. My monitor is set to 240 Hz in Windows, the NVIDIA settings, and each game, and I am using DisplayPort. Occasionally the display seems smooth at 240 Hz, but after a few seconds it goes back to feeling like 60 Hz. I have already replaced both the GPU and CPU, and the issue remains. The main games are CS2 and Fortnite. My system has a Ryzen 7 5700X3D, RTX 5060 Ti 16GB, 32GB of 3200 MT/s memory, and a Gigabyte B550 Gaming X V2 motherboard. The monitor is a BenQ XL2540K.
3 Answers
It would help to confirm whether this is actual refresh-rate behavior or just a frame-pacing issue. Check the monitor's own on-screen refresh-rate display while the problem is happening, rather than relying only on the in-game FPS counter. Also try disabling V-Sync, frame limiters, NVIDIA G-SYNC or VRR, and any game-specific overlays one at a time. A game can report hundreds of FPS while still feeling like 60 because of poor frame pacing or a synchronization setting.
The PCIe link showing x8 is probably unrelated. An RTX 5060 Ti running at PCIe 4.0 x8 in the primary slot should not make the desktop or every game look locked to 60 Hz. I would focus on the display path and settings: verify the monitor is actually connected to the GPU, check the monitor's OSD for its active signal mode, try exclusive fullscreen, and test with overlays such as NVIDIA, Xbox Game Bar, Discord, and motherboard utilities disabled.
The GPU is installed in the top x16 slot. I was worried the PCIe x8 reading might explain it, but the issue also happens after changing major components.
Since you have already tried several monitors and multiple DisplayPort cables, a bad cable or panel is less likely. Try a clean NVIDIA driver installation and reset the NVIDIA Control Panel settings to default before configuring only 240 Hz again. It is also worth checking whether Windows is reverting the monitor to a lower refresh rate after sleep, resolution changes, or launching a game. If the monitor's OSD still reports 240 Hz, record the screen with a high-frame-rate phone video; that can help distinguish real 60 Hz output from stutter or inconsistent frame times.

The monitor and Windows both show 240 Hz, but the motion still looks like 60 Hz. I have already checked that motion blur is disabled.