Makes some sense. I believe the VGA detection is done by probing various combinations of pins as connected or not. If you are good with electronics you can make a VGA terminator following the instructions here:
http://www.mp3car.com/vbulletin/general-hardware-discussion/1763-how-does-video-card-detect-vga-monitor-present.html#post640216 or you can buy one readymade, but at that point you might as well just buy the actual Apple NTSC/PAL adapter. CB Chris G wrote: > Hi, > The funny thing about this is, I have a Mac Mini with the VGA adaptor. > Everything is slow until I connect the monitor. Now here's the funny > thing, I just connected the VGA cable, the monitor is not even plugged > into power. Guess what, the Mac is happy. > Chris > > > > On Thu, 29 Oct 2009 09:59:33 -0400 > Chris Blouch <cblo...@aol.com> wrote: > > >> I'm guessing that the Mac is constantly scanning for monitor presence >> when none are hooked up. With an actual VGA or DVI display hooked up the >> Mac can query the display for information such as supported resolutions >> and refresh rates. So a DVI to VGA adapter doesn't help because the Mac >> is still trying to query the display, and apparently often enough to >> slow everything down. The 'video' adapter lets a mac display on either >> NTSC or PAL television screens. The adapter has both an RCA composite >> and ADB style SVideo connector. Neither of these has any query >> capability and it's not needed because PAL and NTSC are fixed >> resolutions/scan rates. So plugging in one of these adapters stops the >> Mac from polling the display and makes everything happy. Might be a >> hardware level bug with the video controller holding things up while it >> tries to query the non-existent display forever. Apple really should fix >> this so the machine doesn't slow down when no display is attached, but >> they probably consider it an edge case. I wonder what the percentage of >> non-screen mac users is, even among the blind? >> >> CB >> >> John André Netland wrote: >> >>> Esther, >>> >>> Do you know what is the correct adaptor to use for desktop computers >>> like G5, Mac pro etc. I have tried running those machines without >>> monitors but with a video adaptor. It has a flat USB like plug in the >>> other end of a cable, but the plug is wider than USB, common to >>> connect to modern video inputs. This setup did however still cause the >>> Macs to be slow. As soon as the monitors where connected again, the >>> issue disappeared. >>> >>> Thanks, >>> John André >>> >>> >>> On 29. okt. 2009, at 05.05, Esther wrote: >>> >>> >>> >>>> Hi Doug, >>>> >>>> I'll point you to a Mail Archive list post that gives links to the >>>> correct video adapters for both new Mac Mini models (since March 3, >>>> 2009 -- with Mini-DVI ports -- "Apple Mini-DVI to Video Adapter") >>>> and for the older Mac Mini models with DVI ports (manufactured >>>> before Mach 2009 --- I guess your Mac Mini might be in this >>>> category) -- these use "Apple DVI to video adapters. >>>> >>>> http://www.mail-archive.com/macvisionaries%40googlegroups.com/msg02152.html >>>> >>>> The post links to actual product pages in Apple's Store, to avoid >>>> problems. Do NOT get the connector that attaches the Mini to a >>>> Monitor -- unless you really have a monitor at the other end, this >>>> will not help at all. The monitor connectors are bi-directional, so >>>> it is possible for the Mac Mini to sense whether there really is a >>>> monitor at the other end. The video adapter connectors have a round >>>> protruding plug in the connector unlike the flat VGA end of monitor >>>> adapter connectors. The signal only goes outward, so the Mac Mini >>>> gets not input to inform it that there is no video device at the >>>> other end. I don't trust myself to type the product codes correctly >>>> here, but they are correct in the linked post as long as you >>>> correctly identify whether you have a new (post March 2009) or old >>>> (before March 2009) Mac Mini model. When in doubt, Google the Apple >>>> Support page and type in your Computer's serial number in the search >>>> field, and your model will be identified. (Navigate with VO-M to >>>> Apple Menu on menu bar, arrow down to "About this Mac", where the >>>> operating version number is announced route your mouse cursor to >>>> VoiceOver cursor with VO-Command-F5 and click twice with VO-Shift- >>>> Space. Move off and onto this field to read the serial number and >>>> copy it to your pasteboard with VO-Shift-C. Then you can paste it >>>> into a TextEdit window, or you can interact and VO-Right arrow to >>>> just the actual serial number and copy it with VO-Shift-C, then >>>> paste with Command-V into the Support page search field. >>>> >>>> HTH >>>> >>>> Cheers, >>>> >>>> Esther >>>> >>>> >>>> Doug Lee wrote: >>>> >>>> >>>>> I have no compatible monitor at this location, but I just heard of >>>>> some sort of "dongle" that's supposed to fool the machine into >>>>> thinking I have one. Any info on where to obtain such a thing? >>>>> >>>>> On Wed, Oct 28, 2009 at 05:36:22PM -0700, Mac Cougar wrote: >>>>> >>>>> Plug in a monitor for the performance issues. >>>>> On Oct 28, 2009, at 4:48 PM, Doug Lee wrote: >>>>> >>>>> >>>>> >>>>>> Last Friday I installed Snow Leopard as an upgrade of Leopard on my >>>>>> Mac Mini. I also installed the newer Xcode from the Snow Leopard CD >>>>>> over the Xcode I already had. I finally reinstalled the Ports >>>>>> package, though I did not recompile all my ports yet. >>>>>> >>>>>> But I got a number of very nasty surprises that seem uncommon, so >>>>>> I'm >>>>>> hoping someone out there has an idea what on Earth hit the fan here. >>>>>> I have tested the below findings with no ports running as far as I >>>>>> know. >>>>>> >>>>>> Problems include: >>>>>> >>>>>> 1. Safari is hopelessly slow! Navigating from one site to another, >>>>>> such as by typing in the address field, can take a full minute, >>>>>> during which VoiceOver occasionally says, "Safari busy." Similarly, >>>>>> getting to the menu bar with VO+M and moving among menu bar options >>>>>> with arrows can take up to a full minute per keystroke. >>>>>> >>>>>> 2. Typing into any edit control I tried, mostly TextEdit and Skype >>>>>> chat boxes, seems to cause the Mac to get behind, with or (I think) >>>>>> without VoiceOver running. With VO running, if I type reasonably >>>>>> fast, VO loses the ability to say the characters I type, goes silent >>>>>> for a moment, then starts saying "busy" once for each key I hit. >>>>>> I'm >>>>>> used to hearing individual characters as feedback against errors, >>>>>> and >>>>>> VO under Leopard handled that just fine. >>>>>> >>>>>> 3. Though some people claim that commands like VO+F2 for window name >>>>>> and VO+Shift+F3 for Cursor Tracking toggle still work in Snow >>>>>> Leopard, >>>>>> I (and one friend) find these commands do nothing now. I believe >>>>>> the >>>>>> Commands help still documents them though. Removing and making VO >>>>>> rebuild all preference files did not solve this. >>>>>> >>>>>> Any pointers will be most graciously accepted. This machine has a >>>>>> 300 >>>>>> gig drive with only 30 gig free, and I have as yet no device >>>>>> elsewhere >>>>>> with enough free space to afford me the option of a complete >>>>>> backup/format/restore. >>>>>> >>>>>> >>>>>> -- >>>>>> Doug Lee d...@dlee.org http://www.dlee.org >>>>>> SSB BART Group doug....@ssbbartgroup.com >>>>>> http://www.ssbbartgroup.com >>>>>> "When there is no enemy within, the enemies outside cannot hurt >>>>>> you." >>>>>> --African Proverb >>>>>> >>>>>> >>>>>> >>>>> -- >>>>> Doug Lee d...@dlee.org http://www.dlee.org >>>>> SSB BART Group doug....@ssbbartgroup.com >>>>> http://www.ssbbartgroup.com >>>>> "The most exhausting thing in life is being insincere." >>>>> - Anne Morrow Lindbergh {American Author} >>>>> >>>>> >>>>> >>>>> >>> >>>> >>>> > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "MacVisionaries" group. 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