How to Fix a Stuck at 60Hz / Can't Get 144Hz on the AOC Q27G2

Causes

• Windows defaults a new display to 60Hz — the Q27G2 is a 27" QHD VA panel rated at 144Hz, but Windows automatically selects 60Hz the first time it detects a new monitor and never changes it on its own. Most "my 144Hz monitor is stuck at 60Hz" reports are simply this setting, not a hardware fault.
• A cable that can't carry the bandwidth — to run 2560x1440 at 144Hz the Q27G2 needs a DisplayPort 1.2+ or an HDMI 2.0 link. An HDMI 1.4 cable tops out around 85Hz at 1440p, so the 144Hz option never even appears in the list — the cable (not the settings) is the bottleneck in roughly half of these cases.
• Plugged into the wrong monitor input — the Q27G2 has one DisplayPort, two HDMI 2.0, and a VGA port. If the cable is in the VGA port or a low-bandwidth input, the monitor physically cannot hit 144Hz regardless of the software settings.
• Refresh rate hidden at the operating-system or driver level — the 144Hz option can be absent because the display is mirrored to another 60Hz screen, running in a compatibility mode, or the GPU driver hasn't exposed the higher rate until updated or correctly configured in the NVIDIA/AMD/Intel control panel.
• An in-game frame cap masking the change — even with the desktop at 144Hz, many games ship with a default 60 FPS cap (or VSync locking to 60), so gameplay still feels and measures like 60Hz even though the display is set correctly.

How to Fix

1. Use a cable and port that can carry 1440p/144Hz — use the included DisplayPort cable (preferred) or a certified HDMI 2.0 cable, and plug it into the Q27G2's DisplayPort or HDMI input — never VGA. A DisplayPort 1.2+ or HDMI 2.0 link is required for 144Hz at this resolution, so swap any HDMI 1.4 or generic cable first.
2. Set 144Hz in Windows Advanced display settings — go to Settings → System → Display → Advanced display, select the Q27G2, open the refresh-rate dropdown and choose 144Hz (at 2560x1440). If you only see 60Hz here, the cable or driver from the steps above is the cause; if you see it, select it.
3. Confirm and set the rate in the GPU control panel — open NVIDIA Control Panel → Change resolution, or AMD Adrenalin → Display, and set the refresh rate to 144Hz for the Q27G2 at 2560x1440. This guarantees the full variable range is exposed and, on NVIDIA, makes sure FreeSync/Adaptive-Sync can engage across the range.
4. Update or reinstall the graphics driver — download the latest driver directly from NVIDIA, AMD, or Intel (not just Windows Update) and install it, restarting when prompted. A fresh driver ensures the 144Hz mode is exposed; if the option is still missing, run Display Driver Uninstaller (DDU) in Safe Mode and reinstall cleanly.
5. Make sure the display is not mirrored — in Windows Display settings set the Q27G2 to Extend rather than Mirror to another 60Hz screen, because mirroring forces both displays to the lowest common refresh rate (60Hz).
6. Remove in-game frame caps to feel the difference — in your games, set the frame-rate limit to Unlimited/Max or cap at 144 FPS, and turn off VSync where it locks you to 60. If games still measure 60 FPS after the rest of the fix, the game cap (not the monitor) was hiding 144Hz.