Screen intermittently blacking out during gameplay

[timeonmyhands]

I'm posting both the problem and (my) solution as I've seen a number of threads on this and other sites reporting this issue and I hope that I'm helping out by posting this (rather than replying to multiple older threads).

Issue : Screen blacks out at seemingly random intervals during gameplay. Usually on MAME. Blackout lasts 1-3 seconds.
Setup : PI 3b. No overclocking. VGA connection to an older model monitor - like a lot of people I'm using older kit and particularly wanted a 4:3 monitor for my cabinet.

I followed a salad of advice from various threads. HDMI boost and disable screen blacking didn't work at all. Lowering the screen resolution helped in 95% of cases and I identified (by also using a newer monitor that didn't fit my cab) that this was an issue with my older monitor rather than the Pi.

The key was that the blackouts only happened on newer games with large amounts of visual data - big sprites in the X-Men vs Street Fighter games, and lots of large sprites on screen in AvP (both in MAME2003). The Lenovo was basically choking up on certain games at certain points. I tried more than one VGA adapter and no change.

My solution was to buy a HDMI to DVI adapter. A lot of people still seem to be using VGA adapters on older hardware (and last week I knew nothing about passive/active adapters), but if your monitor also offers a DVI port, this seems to be the better option. There are plenty of ex-office refurb 4:3 monitors out there for about £20. Definitely go with one that doesn't need you to use a VGA port.

Hope this is of some use to people.