Visual distortion and the nVidia 5200

[capone]

I'm thinking it's the 5200 card, but recently I started getting a "heat wave" visual effect on the screen (even during bios, so it's not xp). It's only very obvoius on the flat blue GB background. If I shut down for a while, it goes away for a while.

My case runs around 89 F/31 C, and the CPU around 107 / 41 when GB is doing TV. I leave the system always on. That doesn't seem too hot, but maybe the prolonged heat effected it.

Has anyone gotten this before? Also thinking it could be the cable.

[Darx-starz]

Could be a hum bar. Have you tried re-routing your cables? Try disconnecting everything but the video to the TV. If it happens on boot then its not heat. Also your temps are OK

[capone]

Unplugged everything but s-vid, and still there. It may not be an nVidia-specific thing. Maybe I'll grab a better s-vid cable when I go pick up my son today.

[capone]

I thought the temps were ok, too. The HDs get a little hotter (110-118), but it seems like a relativly cool case. I may get some better 80mm fans that can push more air. Noise isn't a big issue where it is in cabinet (ent center w/ open back)....only hear it when tv is off.

The card holder piece of metal between the tv & vid cards is missing to, they have a vent in between them.

[cwills]

capone, if it is a hum bar, you've got a ground loop between devices. I don't know what your setup is, but coax cable is a great source of ground loops, inter-connecting every TV in your house to each other through a common ground. Subwoofers also tend to give you hum bars. Years ago I tried hooking my PC's audio output to my stereo and had a bad ground loop. I ended up splicing a couple audio isolation transformers in the lines and it removed it.

A couple things you can try to test it out. Physically unplug all coax leads in your house from their TV's, or VCR's, etc. Check for the interference, if it is gone, you know it's coming from the coax. You can also "temporarily!" use a 3-prong to 2-prong adapter and plug in your TV&PC into the wall with that, so they aren't being grounded. If after disconnecting the coax leads, and "un-grounding" the TV, PC & everything connected to it, you've still got the interference, then I would definately try better cables with shielding. If the problem goes away after the test, you've got a ground loop and need something like a video isolation transformer to get rid of it. Jenson Transformers sells some great ones, but they are expensive. Their cable TV RF isolator VRD-1FF would probably do the job, but it's about $60. You can get a much cheaper one at Parts Express, but it doesn't have as much bandwidth. For the price, I'd probably just order that one and try it first.

[capone]

That's some great feedback, but I don't think it's a hum bar. If by bar it's straight hoz/vert, then it's different from this effect. This looks like....think of standing in very shallow rippling water, and looking straght down at it. The look of the shadow of the waves on the ground/earth underneath is like the effect. Sometimes it's up/down, but usually it's diagnial. It's almost magnetic-looking.

There are home-theather speakers in the vicinity, but they haven't been move recently, and are at least a foot from the pvr. I'm assuming Sony shields stuff pretty well, or they'd have a hard time selling units.

On the coax I have Motorolla booster and an FM trap after that, but both have been there for a while. The effect is still there w/ coax out.

[capone]

Wasn't the cable...put on a thx s-vid. It looks better, but waves are still there (again, most noticable on just main menu screen w/ that blue static background.

I have a new vid card coming (ati 9200) so I'll know if it was the card itself. I just want to see if it's not broken so I can ebay, if that's the case. I also wanted to make sure what happened to the nvidia wasn't going to happen to ati, if it's something I did.

[capone]

The THX monster wasn't too expensive but still really picked up some color and sharpness, so I agree on good cableing. Management is another issue. When I do new vid card (looks like it's on truck for delivery), I'm going to clean up the bird's nest I have back there.

[capone]

I think I have that splitter, but reqiring the coax would be trickier. I have the Motorolla signal booster, which keeps all the signals consistanly strong. The THX wasn't too bad, $20 4'.

I think where I'm just using analog CATV to a non-hi-def TV, there's a limit to how good it's going to get. At the next tv (read: this one breaks, as they all do), I'm going to step up.

[capone]

I think I found it:

http://www.commspecial.com/10quest.htm
"Most consumer-grade televisions are lenient in accepting sub-standard NTSC signals, so the “cheating” of the scan converter may not be evident to the user. However, problems will inevitably arise when attempting to use the scan converter with other, less-accommodating types of professional video equipment. One of the most common ways a scan converter might violate the NTSC standard is by not locking the colors in sync with the brightness portion of the TV image. This is called unlocking the color subcarrier and will make the colors on the TV appear to wave or “swim,” even on a consumer TV. Once you are assured that a scan converter outputs a true, NTSC (or PAL) standard, you need to evaluate the formats in which it provides this output."

Although they are not specifically talkng about video cards, the logic is the same. I'm not sure why the card would have lost sync (I know you can change in xp, but I doubt it flashes card to do in boot), but the effect they describe it correct.

There's a some good info there nonetheless, and a link at the bottom about computer to video output that was interesting, too.