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I've been running my vt540 off my Radeon HTPC for a few months now, and have noticed an annoying thing. Frequently (80% of the time) when I fire it up, it doesn't seem to get a good 'lock' on the refresh rate (1024*[email protected]), causing shimmering/flickering. If I change refresh rates to something else then back, it usually rock solid.

Also, I can't seem to run at anything other than 60 or 85Hz, 70,72 & 75 cause dark bars to obscure most of the desktop - is that normal?


Thanks,

DJ
 

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Before you blame your PJ try another video card or laptop. I thought the same about my LT150 until I switched from Geforce2 to Radeon VE. Sometimes it could be your video card, drivers, refresh program (Powerstrip is best and Hztool not as good), cables, etc. Remember that it sync with Horizontal and Vertical signals. If these are weak it could screw up syncing. And it's not normal to unable to sync to all those settings. The only one that you may have trouble with is 72 Hz as I and others had trouble at that setting with yellow/brown coloring. 60, 65, 70, 75, 80, and 85 should be fine. 60 should be ideal for most PJ VT540 included. If above not help then call customer service for help.
 

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DJ, I can't say whether or not the problem is with the projector or the computer but I can say that something isn't right. I run my vt540 with a Radeon LE at XGA 75Hz all day long with no such effects. Good luck and I hope it works out.
 

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I've got a similar thing going on with my VT540 / Radeon LE card.


Note: I run it at 60Hz -- seems to give me the best results. Also synchs fine at 70 and 75Hz. 72Hz XGA is not supported on this projector.


I use Mark Rejhon's Pixel Perfect Test Pattern at http://www.marky.com/misc/testpatter...ern_ByMark.bmp as my background wallpaper. See this thread:
http://www.avsforum.com/avs-vb/showt...threadid=21705


When I first power the PC & projector on, the projector synchs & the background is rendered accurately. Within a short time, I can tell from the test pattern that the timing goes out of alignment -- the patterns show interference & sometimes vertical bars. If I re-synch the projector (using auto-adjust button or resetting the synch via Powerstrip), it fixes itself.


Note: I can't really tell that I'm losing alignment by looking at video -- I have to use the test pattern to really see it.


I find that after approx. 10 or 15 minutes, this isn't a problem -- it's just a warm-up thing.


I've also wondered if this is:

a) Normal

b) Fault of the projector

c) Fault of the PC or video card


I really don't want to replace my projector, as it took me A LOT of Insta-Care returns before I got one with all good pixels.


I'd be interested in any other observations on this topic...


Thanks and regards

BB80301
 
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