Recommended video card for projector?

For the past few years our church has been using a projector that is hooked up to a desktop computer. We've always had an annoying issue - whenever the projector is on, there is a faint band that scrolls from top to bottom continuously.

We've been through two projectors so I know it's not the particular brand. Also, I used a laptop to project an image and the band didn't happen. Therefore, I'm assuming it would be the video card of the desktop computer. Maybe I'm reaching but I'm annoyed, embarrased when we have visitors and would like to have this resolved.

Our projector is the Hitachi CP-X444. I've contacted them and they have no clue what I'm talking about. I also contacted them about what kind of video card is recommended - their quote to me was to "contact the computer manufacturer." Now this is silly to me because my Acer people wouldn't know the specifics behind what video card is needed to run a particular projector.

I hope this makes some kind of sense and I'm hoping even more someone can give me a lead.
Thanks so much
dan

 

Greetings, unclebean93...

The 'band' might easily be a mismatch in screen refresh rates - you see it often on television programs that are showing another television or monitor in the background...

Try changing the refresh rate for your Acer (any rate other than 60 Hz, or 50 in Europe)...if you need help doing this, let us know...

 

Thank you so much for this lead. I do not know how to do this. Your assistance would be greatly appreciated!
dan

 

No problem...

Not knowing which operating system you're using, I'll couch this in generic terms:

Right-click on an empty portion of your desktop - click 'Properties' - click 'Settings' - click 'Advanced' - click 'Adapter' - you should now see a drop-down indicator for changing your refresh rate - change it to something higher than 60 Hz (70, 75, 85 - whatever looks best for your preferred monitor resolution) - if the box is set on 'Optimal', change it anyway, because Optimal may be 60 Hz...

You should be able to apply any changes made without rebooting, despite any prompts, but a reboot may be necessary...

Be advised: on later Windows OS's, you may have to navigate to your Display Properties through the Control Panel...

If this doesn't work, or if you have any questions, please advise...

 

A thought: since you said the problem doesn't occur on your laptop, you might use the above path to check your laptop's refresh rate and compare...

 

Caliban,

I do so much appreciate your help in this matter! I will definitely be exploring this route over the holiday. I will let you know what I find out. Thank you for taking the time to help, and not only help but to make sure I understand!
dan

 

Have a safe and happy holiday - good luck!

 

Ok...I'm here at the church - but will be leaving soon - You asked me to check the refresh rate on the monitor...the way the display setting are - there are 2 "monitors" - the one for my desktop and the projector. #1 (main) & #2 (projector) --- Both of which are set at 60 hz -- I can change both to 60, 70, or 75 --- those are my 3 selections. Do I need to change both monitor rates or just the projector rate? I changed the rate on the #2 monitor to 70 hz and that made my #1 monitor display look huge and unproportionate so I changed it back. I'm confused and scared to go on right on without further instruction.

Thanks for your help!

 

Hi, Dan...

Don't be scared: these are only machines...

The reason the display looked "huge and unproportionate" is probably because the resolution needs changing - it most likely reverted to 640 x 480 or 800 x 600...try changing the resolution to 1024 x 768 or higher along with the refresh rate change...

The key here is: did you lose the original "band" problem? If so, then you can always experiment with the refresh rates and resolutions to achieve a good symmetry...if not, we're on a wrong track here...

 

I'm back...

I checked the refresh rates on the computer...changed them to the highest they could go - 75 hz - no change in the horizontal scrolling band issue. With all the troubleshooting I've been doing, I'm starting to doubt myself with what I seen when we used the laptop. Maybe there was a banding issue with it but I didn't notice due to the situation of the service (changing from desktop to laptop to run a ppt program) and having to change so quick that I wasn't focused on it. Maybe I'm reaching.

Let me ask you this...Since this has happend with 2 different computer and 2 different projectors, do you think it could be in the cable itself? We are stretched roughly 80-100 feet from computer to projector. Please don't ask me how the cable is as it's in the attic (about 30 feet up). I don't know how many, if any, extentions there are. I'm using that as a last resort if you think it could be the cable.

Thanks again for all your help!
dan

 

It may be. Check markertek.com for the price on their testers. You can also call them to find out what the price would be to manufacture a cable for the length with signal loss. Bad thing about stretching VGA or RGB that far with out amping it along the way, is that you get signal loss, and it is greater with cheap cables.

BTW, my church is looking at Dell T3500 units with NVidia Quadro NVS-295 cards for two machines that are starting to not handle the use that we put them through.

 

Agreed with brownizs - overly long cables can introduce strange effects...back in the day, I knew the Standing Wave Ratio formulas while working on microwave systems in the Army, but I've long forgotten them...

There's a quick check, of course: hook up a projector with a short cable, and see if the symptoms change...