Member Avatar for xkikix

Hi there,

I am having quite an upsetting problem with a new monitor I have bought and wonder if anyone can help me out.
I do graphics work and so I needed to purchase a larger monitor because I was killing my eyes on the 13inch new MacBook screen.

I needed something affordable and so did some research and stumbled upon the BenQ2220HD monitor. Very good reviews, reliable brand, etc.

Somehow it didn't come with a DVI-D cable so had to purchase it. Purchased a 5m cable, thought this was the norm and plugged it in. The monitor was going crazy, flashes, grey noise, appearing here and there, I tried setting different resolutions, funny thing is that once you got it working it would be perfect but then sometimes would start misbehaving again, or if I turned the screen off and back on again, it would have the grey noise, and take a while return to normal, after much coaxing from me.

Then someone told me the cable is too long, the signal is travelling too far between points so purchased a 1m cable. SO I thought this was my answer. When I plugged it in it was much more stable than with the 5m cable. The right resolution came up straight away and seemed to be alright. So started to play with it, and then noticed these flickering pixels appearing on certain colours, lines appearing where grey bars in the browser were, all sorts of flickers. Sometimes it even goes back to the grey noise, the whole screen. On the whole I guess it is more stable, but when it wants to, and I get the flickering pixels all the time (a weird thing which I didn't have with the 5m cable once I got it to work.)

The monitor came with a disk with cat, inf, and some other file type, must be drivers? Well I can't use them as I have the mac. I tried putting the disk in and seeing if there was anything the mac could read but nothing.

I was thinking, if I install Windows using Bootcamp on here, might that cure the problem?

Sorry for the really drawn out explanation -- it's just, there are lots of things to say about the problem.

Thank you in advance for any help at all; I'm going crazy over this.

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  • Latest Post Latest Post by profmambo

Dani AI

Generated

Short answer: this looks more like a signal/handshake or cable/adapter problem than something Bootcamp will reliably fix. Installing Windows might change how drivers talk to the monitor, but it will not cure a bad cable, a flaky adapter, or a monitor hardware fault. Use Bootcamp only as a last-resort diagnostic — there are quicker tests that will isolate the cause.

A practical, prioritized checklist to follow:

  1. Try the BenQ with a different computer (PC or another laptop) and try the Mac with a different external screen or TV. That immediately tells you whether the monitor or the Mac/adapter/cable is at fault.
  2. Test during startup (watch the Apple boot screen). If glitches appear before macOS loads, the problem is almost certainly hardware or cabling.
  3. Swap the adapter and the cable for short, well-shielded units (try HDMI if the monitor and adapter support it). Poor shielding, damaged pins or a cheap mini‑DP/DVI adapter are common causes of intermittent flicker.
  4. Plug Mac and monitor into the same outlet/power strip to rule out a ground/earth issue.

Mac-specific steps that often help: in System Preferences → Displays hold Option to reveal and click Detect Displays; reset NVRAM/PRAM (restart while holding Option+Command+P+R until the second chime) and reset the SMC (procedure depends on model — use the removable/non-removable battery method for your Mac). Boot in Safe Mode (hold Shift) or run Apple Hardware Test (hold D at startup) to check for GPU/firmware problems.

Tying this to what others observed: was right to check Display settings, and ’s note that reapplying settings temporarily clears the noise points toward an EDID/handshake problem rather than purely bad pixels. If the monitor still misbehaves with another source, ask BenQ for support or exchange; if the monitor is clean with other sources, replace the cable/adapter (prefer short, high-quality, shielded cables or an active adapter) and retest.

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Member Avatar for tje210

cable length wouldn't be the issue. have you tried the diaply setup wizard? go to system preferences - displays. try changing refresh rate, resolution, all that fun stuff.

Member Avatar for profmambo

Having similar issue when plugging in Dell diplay with Macbook Pro 10.6.8.

I am using the display with the Macbook in power saver mode (with USB mouse to enable O/p to ext. display). Every now and then noise appears on the display. I tried different DVI-VGA adapters and cables but the noise continues. Oddly, the noise is cleared when I reapply the display settings. I observe that the display will only refresh at 60hz as others rates are greyed out and not available for this brand new monitor. After a short while the noise comes back.

It appears to be an OS issue although I haven't yet tried using a DVI cable.

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