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aaronvegh
May 23rd, 2008, 12:23 PM
Hi there,
I've had my MythTV box in operation for over a year now. In the past few days I've started noticing a problem with the video output: there is a diagonal streaking or banding effect happening. It looks like nothing so much as driving rain in front of the picture! If nobody knows what I'm talking about I can post a picture perhaps.

I've switched up the cables to test whether the TV or the computer is the culprit. With another video source -- a set-top DVD player -- the picture was crystal clear, leading me to suspect that there is some problem with the video out card.

Is this a hardware defect after so many hours of operation? Or is there a solution in software?

Cheers!
Aaron.

aeiah
May 23rd, 2008, 01:36 PM
if you've swapped cables and still get the same error then its probably the video card. you should check a few other things first before splurging.

what does the computer interface via? svideo, hdmi, component, vga? did you test the dvd player using the same input? (it could just be the tv's s-video being at fault, for example)

have you tried changing resolution on your pc? perhaps the tv is on its way out, and can handle the lower dvd player resolution just fine, but is struggling with the higher pc one?

have you moved anything close to either the tv, the cable or the pc recently? digital cordless phones, speakers, fridges etc can all mess things up

aaronvegh
May 23rd, 2008, 02:15 PM
Hey there,
Great questions! I'm using S-Video to connect the computer to the TV, and sadly my DVD player doesn't have an S-Video out. :-P

As for the resolution: I had it set at 800x600, and moved it down to 640x480. The distortion effect moved from diagonal to almost completely vertical, and it seemed more wavy than rainy.

Cheers!
Aaron.

aeiah
May 23rd, 2008, 04:11 PM
it looks more like interference than a graphics card error, although of course it could be the tv still. did you test with a different s-video cable?

aaronvegh
May 24th, 2008, 04:13 AM
it looks more like interference than a graphics card error, although of course it could be the tv still. did you test with a different s-video cable?

Busy day, sorry for not getting back earlier. I just tried with a different computer connected to the TV using the same S-Video cable, and it displays fine. I think I've ruled out the TV as the culprit. There are also no radio emitting devices that are new nearby... in fact, we've been taking things out of my living room lately.

Seems more likely to be a video card defect, yes?

Cheers!
Aaron.