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I need this information because the two threads below didn't really clarify.

I mean, does a DVI → VGA adapter suitable for the included HDMI → DVI adapter exist? How would I find it? Would it work with an old CRT monitor?

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up vote 1 down vote accepted

Unfortunately it won't work.

The DVI output from a MacBook is DVI-I, containing both analog (DVI-A) and digital (DVI-D) data.

DVI-D is very similar to HDMI bar the audio component (both use TDMS, though the HDMI can use a larger colour space). So HDMI --> DVI-D is simple - electrically compatible.

DVI-A contains analog data equivalent to VGA - again a trivial conversion. So DVI-I ---> VGA is simply choosing which pins to pass through.

BUT

HDMI doesn't contain the DVI-A component so plugging the connectors together, though physically feasible, will simply transmit a null signal.

Sorry.

To get this to work as you want would require non-trivial processing (and all the HDCP fuss) to produce an image and then export in analogue. And would be legally awkward anywhere in US jurisdiction to produce or possess...

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are you talking about mac mini too? And what about that guy that bought a mini-DVI->VGA adapter for macbook? – P5music Sep 20 '11 at 11:48
    
Any recent Apple hardware with a DVI port is sending DVI-I, hence has the analog component for the DVI->VGA. The problem is that the HDMI->DVI only delivers the digital signal. To put it another way, consider HDMI as (-D), DVI as (AD) and VGA as (A-). DVI can talk to either as it's "bilingual"; HDMI and VGA don't have any common ground. – J.C Sep 20 '11 at 12:58
    
cancelled comment – P5music Sep 20 '11 at 14:25

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