connecting new MacBook Pro to projector?

[Commander McLane]

I know that there are some fabulously knowledgable and willing-to-help guys around here, so I'm posting this little problem of mine. I wasn't yet able to get help elsewhere.

I want to connect my laptop (new MacBook Pro 15'', Intel Core i5, NVIDIA GeForce GT 330T) to ordinary VGA-projectors. It used to work flawlessly with my old laptop which had a DVI exit. I used a DVI-to-VGA adapter and everything was fine.

The new laptop has a Mini DisplayPort exit. So I bought a Mini DP-to-DVI adapter and simply added it to the line, which now looks like this: laptop -> MiniDP-to-DVI -> DVI-to-VGA -> VGA cable -> projector. It should work, except it doesn't.

What happens is this: as soon as I connect the plugs and start the projector, the projector is correctly recognized by the laptop as an external display. It shows up in the monitors-menu. If the image synchronization is activated, the laptop's screen resolution changes to match the projector's resolution. If I deactivate the sync, the resolution switches back and I can extend my screen size. In short: on the Mac software side everything seems to be in order, just as I'm used to.

Meanwhile, the projector only ever shows its blue start screen with some "searching for input device" message. No matter what I do, which buttons I press, switching from "PC" to "Video" input and back, I don't get one single step further. For the projector, the laptop doesn't seem to exist.

I had two presentations to make last week, in two different locations, with different projectors, and it was the same both times. Luckily, in both places there was a Wintel laptop available which connected to the projector without any problem, and I could give my presentation from a stick (meaning that instead of a Keynote presentation, I only could one converted to Powerpoint on the spot; which is less than satisfying visually). As it happened twice with different external hardware, the problem must be located either with the MacBook Pro, or with the adapters. But I have no idea what sort of a problem it could be.

So any ideas would be greatly appreciated.

[DaddyHoggy]

Apparently, in one form another - you're not alone!

http://discussions.apple.com/thread.jsp ... 6&tstart=0

http://support.apple.com/kb/ht3492

http://www.avforums.com/forums/apple-co ... stion.html (post #6)

http://www.appleinsider.com/articles/09 ... pdate.html

Apologies if you're aware of these - I'm a non-Mac user...

(but personally with PC machines at work we've found that multiple connectors oft lead to no signal at one end even if they shouldn't!)

[Cody]

Hi McLane... you've probably seen this already, but just in case you haven't, it appears to my inexpert eye that it may be useful.

[Pluisje]

The MiniDisplayPort to DVI cable probably outputs a DVI-D (not DVI-I) signal, so there's no analog signal left to convert to VGA. This MDP to VGA cable will most likely fix it.

[Commander McLane]

According to the product website it should be a DVI-I adapter. However, the product I got from the retailer doesn't look exactly like the pictures, so it's perhaps not original? I'm currently following up with the retailer and the manufacturer.