Blur Busters Forums

Hi, I bought an AOC 24G2U monitor and when using it with a 60hz refresh rate noticed some faint wavy horizontal lines, specially with solid colors like the in the Eizo (https://www.eizo.be/monitor-test/) defective pixels test and uniformity test with 25% grey tone. They are faint but noticeable, crawling across the image.

After some more testing, I found that the monitor fails the lagom inversion test (http://www.lagom.nl/lcd-test/inversion.php) exhibiting noticeable flickering on patterns 1 and 3. If I use a refresh rate over 100hz the problem seems to disappear, but on all the LCD monitors that I tested no (or very minor) flickering is present. Of course none of these monitors are high refresh rate.

Is this normal behaviour of this kind of monitor at 60hz, or of the 24G2U in particular? Thanks!

After a bit of research I found people with similar problems:

https://old.reddit.com/r/Monitors/comme ... aoc_24g2u/
https://old.reddit.com/r/Monitors/comme ... t_to_60hz/

There are also complaints of headaches and eye strain with this monitor, but no specific cause is cited. Can this subtle flickering cause problems even at higher refresh rates where it isn't that noticeable?

After sending it back to the store, an AOC representative said that this was normal for these kind of cheap high-refresh rate monitors. I find this a bit baffling, as there are a lot of great reviews for this monitor in particular, and no mention of this flickering issue. Can someone with this monitor check if they have this problem?

This is true, many cheaper high-Hz LCDs has inversion artifacts. Remember not to confuse "inversion" (the LCD-protecting algorithm) with "inversion artifacts" (visible side effects). Good panel inversion is invisible.

Not everyone is sensitive to flickering.
Some people are sensitive to tearing, others are not.
Some people are sensitive to stutters, others are not.

Thanks Chief! Probably just matter of luck, but quality control seems to be pretty bad for these monitors. My sample flickered like crazy when it went to 50Hz. Just another thing to look out for.

Facing the same issue on my aoc.
The inversion artifacts and horizontal scanlines are noticeable below ~100hz on mine.

The flicker doesn't bother me too much, but the scanlines are insanely annoying. They're mostly visible on shadow-shades like grey or dark blue. Some colors don't have scanlines or artifacts at all. That's why I suspect it's some kind of FRC interference, as RGB[22,22,22] can have very strong scanlines, while RGB[24,24,24] will have almost none and RGB[23,23,23] will have mild scanlines or other artifacts.

The scanlines are dynamic, moving from top to bottom. Their speed is refresh rate independent. Seems to be around 4 pixels/second eyeballing.

60@144hz freesync and 60@60hz look exactly the same.

On extremely close inspection (~10 cm from the screen), the scanlines are part of a bigger also dynamic "checkerboard-square-polygon" pattern. I unfortunately wasn't able to get a good picture of it.

The closer the refresh rate is to 144 the less opaque (visible) the scanlines become, maybe the frc/inversion voltages have been tuned to 144hz, but I'm by far no monitor expert.

http://www.lagom.nl/lcd-test/inversion.php
1 and 2 flicker the most. Even the b&w top menu pictures on Lagos.nl flicker on 50 and 60hz.

I was able to force the scanlines from horizontal to vertical and to be color independent by occupying most of the screen with some inversion patterns while having the service menu enabled.

The service menu doesn't have much to tweak - besides color tuning only 3 options are changeable:
SSC - doesn't do anything
LVDS - doesn't do anything
HW Auto Level - no idea what that is, so not touching it.
There's also a frc test that unsurprisingly states pass.

I contacted AOC support by their online form inquiring if this issue is known to them (not even asking for a replacement or repair) but they politely told me to f* off or get the monitor to their service center on my own so they could see if this behavior is abnormal. Very disappointed by that.

This is my first 144hz monitor, so I thought this might be some GPU, cable or other settings, so when I realized that's a monitor issue I was already out of the return window.

Its a huge bummer for me, as its a very decent monitor besides the scanlines issue, as I was choosing a monitor for both 60hz and 144hz content. I was expecting some shenanigans with 144, but having major artifacts on 60@60hz on an IPS panel is unacceptable imo. So if you're planning on getting it, make sure you'll drive it at over 100hz or aren't bothered with scanlines or other inversion artifacts.

Just wanted to state that 24G2U is the same as 24G2 . Wasn't able to find this thread at first.

The best I was able to capture them:

https://drive.google.com/file/d/1vpdxaT ... p=drivesdk (Frames out of order)

https://drive.google.com/file/d/1Yb3viw ... p=drivesdk (Slow motion video)

I hope the compression didn't mess it up too bad.