The mac mini 2010 produces flickering image on my Samsung SyncMaster 206BW monitor (plugged using the provided HDMI to DVI adapter) : it isn’t obvious overall, however it really shows on some dark gray colors (left side of this site, up and left panes in Garageband). It’s like an old CRT monitor with too low refresh rate. It was ok with the MDD G4 on the same monitor, whatever refresh rate (60 and 70Hz).
Snow Leopard only allows 60Hz on the mac mini (should be ok as it isn’t CRT), and I’m not confident using 3rd party utilities to try to add 70Hz option (some have experienced stability issues or out of range – that requires rebooting in safe mode).
I plugged the power cord on another plug, and also put the LCD display farther, to check for interference problem, however it didn’t help. I also put the original 2×1 Gb ram without success.
I wonder if this is a defect with the Nvidia 320M chipset (or with the added ram, used by the chipset). Usually it comes from a voltage tuning problem when manufacturing the display, and can be detected through inversion test. it was also noticed on some mac book pro. The integrated chipset may so enhance an existing problem.
Update : it seems many people are experiencing flickering problem with the mac mini (varies from monitor vendor, Samsung’s are reported to work bad with the mini). A workaround with previous minis (without HDMI) was to connect to the monitor using VGA (through mini DVI to VGA adapter)… Replacing the mac mini/motherboard many times didn’t work for these people, so they are implying the problem comes from Apple’s driver software (and thus could/should be fixed in a later update) :
The Samsung 206BW doesn’t seem to allow refresh rate above 60hz at 1680×1050, however some have had good result (with other monitors) using 58 or 57hz (using a third party utility). I tested lower resolutions through Apple’s monitors preferences pane, and some provide additional refresh rates (70 and/or 75hz) : for most, switching the refresh rate higher didn’t fix the flickering issue. Moreover, the 1024×768 resolution didn’t experience flickering, even at 60hz, while the “1024×768 (stretched)” (in fact both modes display stretched image) did flicker whatever refresh rate !