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Discussion Starter · #1 ·
I am using the loopback cable with the MyHD card and I am not too happy with the image for dvd playback. My projector (NEC VT540) looks best using a 70Hz refresh rate. I am using an extron distribution amp (1 in 2 out) to send the signal to my projector and monitor.


This projector runs best with a 70Hz signal for dvd playback. If I use the output straight from video card to the distribution amp I get a 70Hz refresh rate just fine. However, when I use the loopback cable it outputs 60Hz eventhough XP reads I am using 70Hz in the display properties under the "adapter" and "monitor" tabs.


Now here is what really has me frustrated. I can boot up with just the video card attached to the distribution amp and again 70Hz comes across just fine. I can then attach in the loopback cable and it continues to output 70Hz.


Can anyone offer any advice about how I can get 70Hz all the time?
 

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"Can anyone offer any advice about how I can get 70Hz all the time?"


JP,


I really don't see how MyHD can change the refresh rate of the desktop because it uses a simple analog pass-thru switch.


What resolution are you using on the desktop for DVD playback? I'll combine that with your 70Hz refresh rate and scope test the pass-thru to determine for sure that MyHD is or is not changing the refresh rate.
 

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PJ,


I can't reproduce this problem with my setup. I rebooted with the loopback cable attached to the graphics card and then measured the H/V Sync from both outputs (MyHD & Radeon) and they are the same frequency.


With the PC monitor connected to the dist amp does it indicate 60Hz? If it does try working back in the chain to determine the source of the freq change by first moving to the MyHD output and they the graphics card output.
 

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Discussion Starter · #4 ·
Thanks for trying to help Cliff. However, I still cannot get anything but 60Hz when the MyHD's loopback cable is being used. This is a fresh install of XP pro also. Here is what I just did as I test:


1. With loopback cable in place I changed the refresh in display properties. In the "monitor" and "adapter" tab they both show 70Hz. I check my projector and monitor. They both display they are receiving a 60Hz signal.


2. I take the loopback cable out of the mix and just plug in my distribution amp to see what the refresh rate is there. It just shows that I am outputting 60Hz.


Here is where it gets strange.


3. Again, the monitor and projector both show 60Hz but XP thinks it is outputting 70Hz. So I leave XP at 70Hz and reboot taking the loopback cable out of the mix.


4. Once it reboots 'lo and behold everything is at 70Hz. Keep in mind this is with the loopback cable out of the mix. I can then plug the loopback cable in and sure enough everything shows 70Hz.


5. This is great of course until I reboot. Upon reboot with the loopback cable in I only get 60Hz regardless.


So with the loopback cable in I can only use 60Hz regardless of what XP thinks it is outputting. With the loopback cable out I can change refresh rates but ONLY when I reboot which doesn't seem right to me.


Part of my problem might be that I am using the default monitor drivers for "monitor." I tried using the "plug and play" driver but that didn't help either.


Does there happen to be a driver which only uses XGA at 70Hz?? This all I want to run for everything except HDTV which I assume with the MyHD it would bypass my video card anyway for this output.
 

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PJ,


Seem clear that the problem is with your video card. Try reinstalling the video card drivers and if that does not fix it for you it's time for a new video card.
 

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Discussion Starter · #6 ·
Hey Cliff. Well, I found a workaround. Good ole Powerstrip. I downloaded the shareware version to see if this would force things for me. It is a little strange because with it loaded I wanted to see what powerstrip saw as the refresh rate compared to the display properties. This is with the MyHD in line. Again, upon reboot the display properties see the refresh rate as 70. Again, the monitor and projector say they are receiving a 60Hz signal. However, when I go to powerstrip it displays 60Hz!! It is in RED though. I have no idea what this means in powerstrip if the refresh rate is in rate but there it is. If I click on the slide bar to change the refresh rate and don't even move it at all it goes to 70 but does not allow me to change the refresh rate. However, once I went and set a custom resolution and saved it I did a reboot. Voila' 70Hz. I wasn't planning on buying powerstrip but if it keeps me from having to go in the back of my computer and change cables everytime I want to switch from HDTV to DVD it might be worth it.
 
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