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120hz Monitor Input Lag Comparison Essay

Whether you're looking for a low input lag console gaming monitor or simply want a PC gaming monitor with FreeSync, the Asus VG245H is a fantastic value. It has virtually no input lag and comes with a ton of features gamers will love.

For PC gamers, it's nice that this monitor goes above 75Hz and supports FreeSync. This adaptive sync technology does a lot of what G-Sync does without the G-Sync cost. Keep in mind, it'll only work with an AMD graphics card.

For console gamers looking for a good monitor, the Asus VG245H is a fantastic option. It has deep blacks, Asus eye care technology to minimize your eye fatigue, and Dual HDMI connectivity so you can have your console and another device on at the same time.

The GamePlus hotkey is useful for all types of gamers. It's a hotkey you can use to give you in-game enhancements.

Overall budget-minded gamers should definitely be looking at this monitor. For PC gamers looking for a cheap FreeSync option, it's a no-brainer. Console gamers can definitely find something cheaper that will work; however, not with as many options.

Coming soon: How to build your own Arduino-powered input lag meter using a photodiode! No soldering needed. Cable latency accuracy of +/- 1 microsecond and input lag accuracy of +/- 0.1 millisecond (once zero-calibrated with a CRT display first on the same system).

Screenshot of early prototype.
New system now has 3 flashing squares, full screen, no title bar.

Even the operating system latencies (e.g. Windows compositing, double buffering) does not appear to matter, provided you zero-calibrate with a CRT first, keep using the same graphics driver, and the window is always centered. The relative input lag latencies stay accurate to +/- 0.1 millisecond. You simply place the photodiode on the screen, and the software detects when the photodiode is pressed against the screen.

EDIT: New version of Blur Busters Lag Tester no longer requires CRT for zero calibration!
EDIT2: Cable lag now reduced to less than 1 millisecond, via a Teensy 3.0!
EDIT3: New version now has three flashing squares, similar to a Leo Bodnar unit. However, the big advantage is that the Blur Buster Input Lag Tester will work on anything a computer can output, including 4K, 120Hz, 85Hz, 2560x1440p, even laptop LCD’s.