I hope someone here can help.

I have a new mac mini with core 2 duo and dual video outputs - mini DVI and mini DP.

HDTV is sharp aquos LCC5255u

Connected via HDMI cable and miniDVI to HDMI adaptor (while waiting for mini DP to HDMI adaptor).

Alternates between connecting regular computer monitor and TV.

The first time I tried this, I just unplugged the monitor and plugged in the sharp to the miniDVI port and it just worked. I had great 1920 X 1080P, 60 hz picture on the sharp. The Mac auto detected it and changed resolution automatically.

When I was done admiring it, I disconnected the sharp and reattached the monitor.

The next day when I tried again, the sharp screen was blank. Occasionally if I restart the mac the sharp says 'signal not compatible", but usually it is just blank.

I have since, zapped the PRAM and NVRAM, reset the SMC, started up in safe mode, deleted the windowserver plist files, started from installation DVD. ALl blank.

Tech support talked me through a system init/reset of sharp - no effect.

Changing inputs on the TV - no effect.

Tested the input and HDMI cable with the cable box and they are fine.

VNCd in to the mac and confirmed - It detects the Sharp and changes the resolution - but sharp screen is blank.

Changing resolutions while VNCd in has no effect.

Got SwitchResX and played a little, but have no idea where to start. The default settings for the sharp look benign.


So....


Is the problem likely to resolve itself when I get the miniDP adaptor and attach that way?

If all else fails, is VGA connection likely to work?

What can I do now to get this HDMI connection working?

The weird thing is how it worked great the very first time.

Here's a longshot that you can try.

Go to System Preferences/Displays.

Select the checkbox to show the Display icon on the menu bar.

Then select the Display icon on the menu bar and look for an option to show the "last 3 resolutions" or something like that.

At this point, you might have several instances of 1920x1080 60hz. Choose one or the other.

Of course, with a blank screen, you have to do this via VNC, but you mentioned that you have done that already, so it shouldn't be hard.

Good Luck!

I don't have any advice for you, other than to suggest display connections from a computer to an HDTV aren't always designed to be hot-pluggable/hot-swappable like a CE device. I can be as cavalier as the next person, and in practice disregard this occasionally, but, if it turns out that you do get past this, rule out a hardware issue and successfully re-establish a connection, perhaps pay more attention to this? Don't just yank out and switch connections "hot." Sharp HDTVs, just in general around here, seem to be of the "more prickly and more difficult to deal with" variety rather than the "just seem to work" variety.

Which miniDVI to HDMI adaptor are you using?

Thanks for the advice.

All my cables and adapters are from Monoprice.

I am not going to work on this anymore until I get the Mini DisplayPort to HDMI adapter and then I will post an update.

I'd guess a bad Mini DVI to HDMI Adapter based on everything you have described.

Yes, thats up there on the differential diagnosis. Its odd it tanked after one use, but the other possibilities seem to require unlikely interactions between this particular TV and this particular Mac.

If thats the cause, the MDP to HDMI adapter should fix things.

If not, I will try some other things - VGA, another mac with DVI to try to further isolate the problem.

So, the minidisplayport to HDMI adapter arrived today and it works! The TV is displaying my mini again, at 1920 x 1080p. This holds up through restarts and all.

So most likely the miniDVI to HDMI adapter I was using was flaky.

Now I have a new problem.

In Mirror mode, the HDTV is limited to the resolution and 4:3 aspect ratio of my monitor.

Is there any way to mirror with different resolutions
' Is this something switchResX can do?

No, mirroring means the same formats on both displays. It's a greatest common denominator thing. Run them in extended desktop mode instead of mirroring. Then both the TV and the monitor can run at their optimum resolution.