Radeon 8500dv Electric interferance

[Afroman]

I have a 8500dv and i get horizontal white lines scrolling the screen.. can be seen more on black background.. whats the best way to stop this??

[JoeTheDude]

You need to unplug your Cable TV from your VCR or TV because that's what is giving you the interfearance.

[Afroman]

i did and thatsmakes it worse.. better sheilding? or do i need to ground my case?

[Ethereal]

I have the exact same problem. I've unplugged all components from the TV so there can be no interference but it's still the same.

I'm using a Jetway OEM Radeon 8500 and was wondering about the build quality of the thing as my old ATI Radeon 64 DDR VIVO worked perfectly.

Can anyone confirm that their ATI Radeon 8500 gives perfect picture quality.

[MikeV]

Check the outlet you have the computer plugged into. Make sure you have less than .5vac between the neutral and ground. If you don't get an electrician to check out your wiring and ground. The rolling white lines can also be caused by an overloaded or going bad power supply.

[drak23]

You may have a ground loop. This is fairly common whenever two sets of electrical equipment which are grounded in different outlets are connected. It can also manifest as a buzzing or humming noise. This happened to me when I ran a long coax cable from my entertainment center to my PC. If you can plug your equipment into the same surge or UPS so that it is grounded via one outlet it will fix the problem. If this is not possible then sometimes it can be fixed with "ground breaker", but they don't always work.

http://www.hometech.com/video/atten.html
(Xantech 63400 Ground Breaker)

This worked for me. If you get one, be sure to test on both ends of the coax cable before you give up on it...

Hope this helps,
Drak

[dmonty]

Here is yet something else to consider.

Your video signal may be too strong and may require attenuation (signal lessening). Do you use video amplifiers/boosters? The ATI Radeon All in wonder family uses a digital TV tuner that is VERY sensitive to signal amplification. Even if you don't have an inline amplifier in place the signal being received from your cable TV company may be too strong. This is usually done to two reasons:
1) Most cable lines run parallel to electrical power lines. A strong signal (combined with shielding) would prevent line noise (electromagnetic interference).
2) A strong signal would also compensate for long cable runs (signal lessening resulting from distance).

If you are like most people then you probably have several video devices connected to the same cable line. (i.e. Splitter to 2 or more TVs + VCR + whatever + ATI Card) When devices are connected to the same cable source each device in the chain attenuates (weakens) the signal by 3db to 6db. If your ATI looks better when the signal is weaker then you have a signal that is too strong. I would recommend buying a pack of signal attenuation pads (about 15$) (Try http://www.smarthome.com/7800.html) You might be able to find some at Radio Shack. I had to do this myself since my ATI would not work in my house without them.

Hope this helps...

D

[Ethereal]

Thanks for that. I may give it a go. But my "old" Radeon worked in the set up no problem. It gave perfect picture and sound. It's only since I "upgraded" to the 8500 from the 7200 that I've had problems.

BTW My PC is in the bedroom and I transmit the signal from the TV out via a Philips video sender, to the front room. So they cannot share the same power supply. This setup uses the S-video out of the Radeon into a scart connector on the Philips box. The signal is then sent to the box in my front room and passed to the tv via a SCART cable. I've tried unplugging and powering down the other components on my system but to no avail.

[MikeV]

Try connecting a cable directly up to your TV bypassing the video sender. Most of the wireless video units run in the 2.4ghz range and are affected by microwave ovens, wireless telephones, walkie-talkies, and all sorts of other new gagets that have hit the market recently. I used the X-10 version of the wireless sender and every time we would turn on the microwave the picture would become scrambled, with white streaks, loss of sync, and color. They are great for limited time usage, but not for permanent installations. I now use mine while installing video security cameras.

[drak23]

Ethereal:
Cool set up! I've been thinking about how to get my TV-out connected to the TV (so I can play back DivX recordings on the big screen). S-video only goes about 15 feet. I was considering coax, but I'll take a look at a transmitter.

FYI, turning equipment off will not break a ground loop - you have to unplug it. One thing you can do to test is buy an ungrounded adapter for one of the outlets involved in the loop. Unplug everything else, use only for testing and make sure it is connected to the equipment that is grounded. Probably overkill but better safe...)

Drak

[Ethereal]

BTW If you're interested in a video sender I got mine from Tesco superstore. It was £50 cheaper than anywhere else at a bargain price of £99 for a Philip one.

You can get other version cheaper but I'm pleased with mine.

It's not the box itself that causes the problem as I swapped to the old Radeon a few times and it worked perfectly.