Help! VERY wierd problem. My LCD (DVI) won't work without something connected to the VGA. What's Going On???

[SuperWrat]

(this was posted first in Technical Support)

I took a friend's old Compaq FP700 15" LCD monitor and also bought a Pine Excalibur GeForce2 Ti video card with both VGA and DVI inputs... for what I 'thought' was a DVI connector on the LCD monitor. THEN I discovered the LCD monitor used an old digital connection/interface called "DFP," not DVI. So I bought a DFP to DVI adapter that made the monitor compatible with the DVI input on the video card.

Now, when I start the system, the boot screens appear on the LCD, but AFTER the first WinXP spalsh screen (with the moving/scrolling dots below the logo) and just BEFORE the blue "welcome" screen for WinXP, the LCD screen goes blank!! At that point, If I plug in another monitor with a VGA connection, WinXP shows up on the VGA monitor and I can navigate display properties to switch back to the LCD monitor!! At that point, I can also unplug the VGA monitor and the LCD monitor will continue working properly.

It gets wierder... If I keep both monitors plugged in when I start the system, the boot screens show up on the VGA monitor... but then after the first WinXP splash screen it switches and displays properly on the LCD monitor! Although this makes the LCD monitor work, I would hate to always keep a VGA monitor plugged in just so I can use the LCD. **** The VGA monitor doesn't even need to be on and doesn't even need to be plugged in to a power outlet for the LCD monitor to work in XP!! (The LCD monitor still won't show the boot screens though, but I don't mind that too much.)

btw, there is no dual monitor support on the video card. Also, I tried plugging in only a VGA cord into the video card... doesn't work... the LCD shows boot screens and blanks before entering XP.

So I'm confused... is this a problem with:
1. the monitor (maybe since it's native connection is DFP
2. the video card
3. WinXP

I would really appreciate if anyone can give me feedback, I've spent considerable time figuring this stuff out and it would suck to end like this. Or does anyone know who I can ask? Or... does anyone know why an unpowered monitor plugged into the VGA port will act as a hack solution, and how do I replicate that VGA connection without a huge monitor? (like I said, I already tried plugging in just a VGA cable) My friend said that maybe the VGA monitor has a closed circuit or even a battery inside that makes the video card aware of a connection.

Help? Suggestions? Thanks!

-Derrick
dvan@uclink.berkeley.edu

 

[arcenite]

Sounds like windows is Defaulting to the analog port. Not sure how that works. Just try to get a DVI->analog adapter. Be kind of funny to have two adapters on one plug, but still, it should serve it's purpose

Bill

 

[SuperWrat]

I read that converting digital to analog is not recommended, but that does sound like a plausible solution. I'll try that if I can't figure out another hack solution, thx!

 

[arcenite]

See if there's a way to change the default... output for lack of a better word, in the control panel.

Bill

 

[SuperWrat]

Originally posted by: aRCeNiTe
See if there's a way to change the default... output for lack of a better word, in the control panel.

Bill

When WinXP doesn't appear on the LCD, I can use the VGA monitor to go thru display properties to switch the output (and thus the monitor) from Analog (VGA) to Digital (the LCD). Unfortunately, this setting doesn't become permanent for some reason, which is why I must always keep the VGA monitor plugged in for the LCD to work.

Is there another control panel setting (besides display properties) where I can adjust the "default monitor?" Maybe somewhere under Device Manager, but I keep getting the same options that I get under display porperties.

Thanks for your help!

 

[arcenite]

Maybe try getting the DVI-Analog connector, but not connecting the monitor to it. What happens if you just connect that adapter to the analog slot, maybe that'll serve the same purpose as your CRT monitor?

Bill

 

[SuperWrat]

Originally posted by: aRCeNiTe
Maybe try getting the DVI-Analog connector, but not connecting the monitor to it. What happens if you just connect that adapter to the analog slot, maybe that'll serve the same purpose as your CRT monitor?

Bill

I already tried connecting a VGA extension cable to the VGA port, and the card didn't detect it... do you think that the adapter would work differently? I believe that there's something unique about a monitor so that even in its unpowered state the vidcard will detect it as a "live" connection. I'll consider trying an adapter... but today I'm gonna test the video card on a friend's system (with a true DVI LCD monitor) to determine whether the vid card is the problem or not.

my other link generated a very brief discussion, i dunno if other people's suggestions make sense.

Thanks!

 

[SuperWrat]

And just to justify why I wanna test the vid card and not the monitor... this monitor worked well for 3 years on my friend's system, so I don't really have any reason to believe the monitor is suddenly faulty, especially with the wierd problem I encountered.

If I had enough cash to blow I would buy a DFP video card from ebay (I can't find it less than $100 anywhere else) since I think that would help. But for the future (since I may upgrade the monitor), buying a vidcard with a DVI connection makes more sense than DFP.

 

[SuperWrat]

I believe I figured out a hack soultion today... basically, I determined that when the LCD monitor goes blank, it's because for some reason the video card doesn't detect it. In fact, when I use the VGA monitor to switch to the LCD, I hafto turn the LCD off and on again in order for the LCD option in display properties to appear. So I reboot the system, and tried turning the monitor off and on repeatedly around the time it goes blank... and somehow WinXP will load on the monitor now!!!

I don't know why the vidcard won't detect the LCD properly, but at least now with my solution I don't need a chunky CRT sittin' around to use the LCD ;-)

I'll test the vidcard on a friend's system to see if his LCD (with a native DVI connection) has the same problem. If it does, I guess it's time to make a return!