Mac Mini dual core 2.66 mid-2010 screen flashing on every 5 seconds

[pincrete]

I have a Mac Mini dual core 2.66 mid-2010 (Geforce 320m graphics). It is left on almost constantly as it is up/downloading stuff using torrent, Recently, if it is left on but 'idle' (ie not actually processing or playing anything, simply working in the background), the screen flashes on every 5 seconds when 'woken'. It doesn't do this if actually working ie moving from site to site on the net, or playing a video. It does this even if energy saver settings are put to always on - ie not sleep or shut down. Screen has HDMI connection.

Normally, switching off, leaving a few seconds, then rebooting fixes the problem, Today, despite being switched off for several hours, it is still doing it. I've tried resetting PRAM but no good. Is this probably the graphics being 'on the blink.

 

[chscag]

That sounds more like a bad or intermittent cable. I have no idea how long you've been using the same cable to connect your monitor to the Mini, but your Mini is 10 years old. Swap the connecting cable to the monitor before trying anything else. If the problem persists after using a new cable we can try something else.

 

[ferrarr]

Are you using the HDMI port on the Mini, or are you using the Mini Display port with an adapter? Can you test the other port? Can you test with a different display/monitor/TV? Also try the SMC reset?

 

[pincrete]

That sounds more like a bad or intermittent cable. I have no idea how long you've been using the same cable to connect your monitor to the Mini, but your Mini is 10 years old. Swap the connecting cable to the monitor before trying anything else. If the problem persists after using a new cable we can try something else.

Cable is fairly new, but I will try another one ASAP

 

[pincrete]

Are you using the HDMI port on the Mini, or are you using the Mini Display port with an adapter? Can you test the other port? Can you test with a different display/monitor/TV? Also try the SMC reset?

HDMI, no I can't currently test the other port as I don't have an adapter.

I tried a SMC reset, after several attempts, it worked, but problem returned. Again, after further resetand cool down period, the Mini is again working but previous experience suggests the problem is going to returm?

 

[chscag]

HDMI, no I can't currently test the other port as I don't have an adapter.

You need to try using the other port as the problem could well be the HDMI port or connector. I know all this troubleshooting and swapping cables and ports can be a pain, but there really is no better way.

If the same symptoms occur when using the MiniDisplay Port output to your monitor, then, you need to consider that it could either be your graphics card in the Mini or the monitor you're using. If you happen to have another monitor handy, we suggest trying that in place of your current monitor.

 

[krs]

I know all this troubleshooting and swapping cables and ports can be a pain, but there really is no better way.

And I would suggest that you keep written notes of exactly what you have done.
After you have swapped cables and ports a few times, it's sometimes hard to remember exactly what was tried already and the results, especially if you get interrupted during that process.
Been there - done that.

 

[pincrete]

You need to try using the other port as the problem could well be the HDMI port or connector. I know all this troubleshooting and swapping cables and ports can be a pain, but there really is no better way.

If the same symptoms occur when using the MiniDisplay Port output to your monitor, then, you need to consider that it could either be your graphics card in the Mini or the monitor you're using. If you happen to have another monitor handy, we suggest trying that in place of your current monitor.

Unfortunately I live in a country where obtaining Mac bits is difficult, so, while I do have access to another screen and another HDMI cable, getting an adapter will involve ebay and waiting for delivery from abroad. However, since having a MiniDisplay Port adapter will be good anyway, I will get one.

 

[ferrarr]

And your model Mini supports audio as well, so make sure the adapter does as well.

 

[pincrete]

I tried a SMC reset, after several attempts, it worked, but problem returned. Again, after further resetand cool down period, the Mini is again working but previous experience suggests the problem is going to returm?

It now takes several (sometimes 4) SMC resets to get it to work ... it does eventually and continues for as long as it is 'active'.

 

[pincrete]

It now takes several (sometimes 4) SMC resets to get it to work ... it does eventually and continues for as long as it is 'active'.

OK, it was getting harder and harder to get it to work, it took multiple SMC resets, then it would suddenly and mysteriously start and work OK while I was actively browsing or 'doing things', I was beginning to be convinced that the logic board or graphics were failing . Finally I managed to try the Mac Mini on a different HDMI monitor (at work rather than at home). Turns out it was the monitor all along, nothing to do with the Mac or cable. I still don't understand how that could be, but it was and the old monitor behaved the same on several PCs as well as the Mac.

 

[chscag]

Thanks for posting back the solution.

Remember what we recommended?

If you happen to have another monitor handy, we suggest trying that in place of your current monitor.

Anyway, glad you resolved it.