Really wierd video flicker

[Nuke95]

I just got a new computer from ABS. I have an Athlon XP 2100, ASUS A7V333 motherboard, and 256mb of PC2700. The video card is a PNY GeForce4 TI4400. I am using an Optiquest Q95 monitor. I have downloaded all the latest drivers.
When I have the refresh rate set at 60hz the image looks fine. Whenever I set the refresh rate to greater than 60hz the image on the monitor looks like it is wiggling from side to side very rapidly and there is some flickering of the brightness. The problem is worst when I have the refresh rate at 70hz. It gets better as I increase the refresh rate but is still not perfect. This problem happens at all resolutions.
I tried an older Dell 17 inch monitor and it did the same thing. When I moved either monitor down to the floor the problem was greatly improved. Not perfect but much better. The same improvement occured in both monitors. When I retested them on the desk the problem returned. Both monitors work fine with the old Dell computer that I have.
I tried moving the monitor and computer to all different positions. I moved the entire desk to a different side of the room. I moved the system into my room. The problem was always worse when the monitor was on the desk than on the floor.
I did not have any problems when I was using the old Dell computer in the exact same location with the exact same desk.
I disconnected all of the other equipment. I moved the speakers away. I moved the printer and scanner away. I even tried moving the mouse and keyboard away. Nothing helped.
I do not think the problem is with the monitors because they both show the exact same problem. The older monitor has worked perfectly for years and both of them work fine with the old computer. The only thing I can think of now is that there is a hardware problem with my new computer. I called ABS and they are sending me a new graphics card. This problem is driving me crazy.

 

[phsstpok]

Try moving the monitor's video cable away from the power cable. They can cross but don't let them run side by side.

The only other thing I can think of is an electrical motor causing it, like a nearby fan.

<b>I have so many cookies I now have a FAT problem!</b><P ID="edit"><FONT SIZE=-1><EM>Edited by phsstpok on 05/10/02 09:18 PM.</EM></FONT></P>

 

[Nuke95]

I already tried moving the cables and components all over the place. The only thing that helps somewhat is if I put the monitor on the floor. It's like the desk is causing some kind of interference but its just a regular wooden computer desk. Its the same one I used with my old computer with no problem. My new computer is at least one factor in this problem.
Thanks anyway

 

[phsstpok]

Re-read your post and realized that I've seen the exact symptoms.

I've seen this when I had my case open and propped an A/C box fan half-way in the case. At 70hz it was wiggling side to side like crazy and kind of fading in and out. It was less severe at higher frequencies. At 60hz it stopped.

OK, I duplicating this right now. Well it isn't quite the way I remembered. I wouldn't call it side to side but rather in and out. It is really bad at 70 hz. At 75 hz it's faster and wiggles more but not as irritating (can't really explain that better except it's like motion sickness). No wiggle at 60hz. I have to change resolution to go any higher than 75hz.

Does this help you in any way?

Is there anything near your video card that could be causing interference?

<b>I have so many cookies I now have a FAT problem!</b>

 

[Nuke95]

I've removing every possible source of interference I can fine and moving the computer all over the place. I even tried adjusting the central airconditioning, as the computer is near the unit. I may try moving the entire system downstairs and trying it there. Both of the monitors worked fine on the old Dell that is downstaits.
Could there be a faulty component in my computer causing the interference. It cannot be only an outside source because my old computer worked fine in the exact same location with the exact same locations.
I saw an older post by "Pottie_trained" and he had the exact same problem I have. I could not find his email address. Does anyone know who that is? Nobody offered him a real fix. I downloaded the program "PowerStrip" which lets you fine tune the display properties. I increased the refresh rate in small increments. At around 60.1hz the screen would slowly start to move back and forth like a wave. As I increased the refresh the wiggling got faster and was less bothersome when I had a very high refresh. The symptoms of this problem sound just like the interference from your fan but I don't know of any outside source of interference.

 

[Nuke95]

My video seems to be working normally now. I have not changed ANYTHING. I used it this morning and I had the problem. Then I turned off the computer. I just got back around 630 and turned on the computer and everything seems to be working normally. I'm using it at 75hz right now. I cannot see any "shaking". My eyes feel a little strainned but its probably just the placebo effect from knowing I have the refresh at 75hz. Normally I leave my computer on all night and day. I just turn off the monitor when I am not using it. Could heat build up be causing the video problems? I hear that the PNY Gf4Ti4400 has worse than average heat dissipation.

 

[Nuke95]

AH! Immediately after that last post I went down stairs and came back up. The image was shaking again. I had the change the refresh back to 60hz. The computer had probably been running for 10 minutes at that point.
I'll try to reproduce the problem. Someone has to have some idea of what could be causing this. Help! I'm going nuts.

 

[phsstpok]

I don't know of anything that is inside the computer that should cause this. I doubt DC fans can do this but you could trying leaving your case open and disconnecting the case fans long enough to test.

From your description it just seems like it has to be something AC and 60hz. How about a transformer from a peripheral, a cordless telephone base unit, a calculator, etc?

If there's nothing close to the computer could there be anything on the same electrical circuit causing your problem?

I can't think of anything else.

<b>I have so many cookies I now have a FAT problem!</b>

 

[lisabob2]

Have you tried replacing the monitor power cord?
Maybe your video cord from the monitor has some damage wires?
I know my monitor acts like that sometimes, and when I wiggle the cord that goes to the video card it stops.
(I have to take the monitor apart to replace that cord so I will just buy a new monitor when this on goes finally,)
Bob

 

[Nuke95]

I don't think there is anything wrong with the monitor I am using. I tried another monitor on this computer and both of them had the same problem. Also, both monitors work properly on a DIFFERENT computer.
Lately when I have been leaving the computer off overnight, it will work properly at all refresh rates for a period of time. Then after a few hours the problem will start without me even changing anything.