What factor causes shimmering of monitor??

Optimummind

Hi,

I was wondering if anyone has an idea as to why my monitor screen has a shimmering effect. Currently these components are overclocked in my system:

1. CPU: If upped the FSB to 152 for an effective clock rate of 2.73GHz from 2.40GHz stock. So, the overall FSB speed is 607MHz from 533MHz stock. BTW, the CPU is being cooled by Koolance Exos water block and idle temp is around 32-33 C at 2.73GHz. Under load, it goes up to 35 C.

2. RAM: Since the FSB has been upped, so has the memory with it. Memory is running at 190Mhz from 166MHz stock for a total overall speed of 380MHz.

-My videocard is not overclocked and being cooled by a copper fan and copper memory heatsinks.

-The northbridge was getting really hot so I replaced the default passive aluminum heatsink with Swiftech's MCX 159-R northbridge cooler which has a copper base with helicoid aluminum rods. The MCX-159-R also has a fan on top which moves around 6.3CFM with a fan speed of 5200 RPM.

Games and benchmarks run fine without resetting the computer or exiting the programs suddenly.

I dont' know if "shimmering" is the correct word but my monitor displays an effect like that found in movie shots where a desert and its heat wave is being shown. You know how in movies, the shot of the desert sand have heat waves slowly moving up and down? It's kind of like that.

I don't know how to get rid of it and which part of my system I have to underclock.

Logla

I wouldn't really have though overclocking would cause this.

When you say shimmering, does this mean that the screen is distorted? It may be the refresh rate of the video card being set incorrectly. I would set this down to 60Hz and work up just to see if that has any effect.

Also, if you set everything back to stock, does the shimmering go away?

And do you have the option to lock the AGP frequency to 33/66 when overclocking the FSB.

Optimummind

The screen isn't distorted but it does have that "hot desert" look. You know how the desert sand gives off heat from the sun and whatever appears above the sand has the wavy look? That's kinda how my monitor looks right now although not as severe as the desert heat wave effect.

Also, my monitor is currently set at 75Hz at 1024x768. And yes I did set the AGI/PCI lock at 66/33MHz.

I'm gonna try to reduce the refresh rate to 60 and see if it goes away.

BWX

I got this sometimes before I put my 9700pro on it's own power lead- Also fans too close too it did this for me-
Also- is the fan on your v-card plugged into the video card? If it is, try unplugging it and putting it on it's own lead.


I ran out of clean leads so I ended up running a dual PSU settup- problem gone forever- All my case fans and the video card fan(s)-- ( I have 2 on there)- are running off a totally separate PSU.

Microwaves running in a house will case this too- at least in my house.

Some monitor manufacturers actually recommend turning your monitor 45 degrees at a time to see if it changes the picture or solves problems-- Not many people have heard of this I am sure, but it has to do w/ the magnetic forces produced by the earth. I guess the say pointing a monitor East or West is better than North or South. Or maybe the other way around, I can't remember, but it's worth a shot..

What really made my monitor wig-out on my 9700pro, was plugging it into the same lead as two hard drives- When I first got it, I just plugged it in to the first one available- I got allot a interference sometimes- other times none..


Also try moving your cables from your monitor around- plug them in and hold them up in the air- put them under your desk/table-- wiggle the connections too, make sure they are in firmly.

Also try to keep your Power lines and video signal lines separated as far as possible and see if this helps.. I've experimented with every one of these things more than a few times to see what would happen, watch your monitor closely while you do these things and look for changes. If you see one, whatever you are doing at the time is at least partly to blame.

Also try plugging in your monitor's power line into a totally separate outlet. Eventually you will find the cause.


*edit- also try turning OFF DCC under "display"- in the ATI control panel- that really helped me out too- My monitor is as solid as a rock now.

Logla

forgot to ask, is this a 2d or 3d issue?

Logla

I forgot about that - had a similar issue with my 9700pro. I got a flickering in 2d with 2 case fans on the same 12v supply. Changing the fans to higher quality ones made all the difference.

Optimummind

This occurs most obviously in 2D. Whether I'm viewing my desktop or reading posts in Driverheaven.net, I get this shimmering effect. I just reduced the refresh rate to 60Hz and Degaussed my monitor but it didn't make any difference. I even tried to up the AGP voltage to 1.6V from 1.5V but no difference again.

BTW, the GPU fan is connected to its own lead on the motherboard and not to the one on the videocard board. The power cable, however, is hooked up to two hard drives. So, I'll try to change the power connections.

As for system fans, I have two fans in the front of the case--one 80mm fan on the bottom front and a 120mm fan in front of my main hard drive. On the back, I have one 80mm located near the CPU waterblock. As for my PSU, I have 2 fans--one above the CPU waterblock and one that exhausts the air outside my case.

Finally, the last fan is the one on the northbridge (Swiftech MCX 159-R).

Well, I'm gonna try now to switch the power source for the Radeon.

BWX

I forgot- Degauss your monitor after it's been on for a while, especially if you have speakers around it- and if you have speakers around it (even if they say they are sheilded)- move em away and see what happens..

Optimummind

Man, I love you guys!! It worked!! That annoying "desert shimmering" effect is gone!!

This is what I did after reading your advice.

Frist, I ran the Radeon power cable to its own dedicated connection.

Second, I took out my 2nd PSU (Antec 400W) and connected all of my fans to it.

Thx guys!!

Optimummind

Darn..the shimmering is back!!

Could this is caused by having too many fans inside the case? I only got 2 in front and 1 in back. Could it be the northbridge fan spinning too fast??

BWX

You know you can make that psu come on at the same time as the main one right? Splice into the green "14" I believe, then any ground to any ground. Presto, dual PSU's in synce with each other! Leeave the second one on and it will turn on with the first one.



If you are going to do this, let me make sure those are the right wires, I just think those are the ones from memory.. There are a few threads from me and a few other people here that did it too (somewhere)

BWX

Did you try disabling DCC in ATI CP? I doubt it's the fans now man.

Also maybe unhook v-card fan and splice it into a separate PSU lead?

Optimummind

Yes, the DCC is disabled. In fact, that option is not even highlighted for my system.

Currently, I have to manually turn on the 2nd PSU by flipping the switch on the PSU. The wire for "jumping" the 2nd PSU in on pins 4 & 6 (that instruction came with the Koolance water system manual).

The shimmering did lessen, however, when I took off the fan on my side-panel.

Optimummind

Ok, here is another update. I set all of my components to their default settings...still no difference whatsoever.

Logla

I'm reckoning this could be EM interference. I doubt very much now that its the fans. What electrical items do you have near your monitor and/or pc. Is there a TV set nearby or even an amplifier. I remember having an old Pioneer HiFi amp and when I got my first pc, decided to put the monitor on top of that (small room - no space). Damn thing went crazy - took me a full day to figure out the problem.

Optimummind

I'm beginning to suspect my room's ambient temp as the cause. I turned on the AC is my room and the shimmering mostly went away. I also took off the fan on the side panel of my case.

And, I'm still running a dual-PSU setup with all case fans and videocard fan hooked up to the 2nd, external PSU.

Could it be that my monitor outside was overheating or my components inside?

BWX

I never thought of that, but when I saw the worst shimmering on mine it was always hot.. I have AC in the room it's in now, and it never does it anymore- I've heard of people putting a fan in the top of the monitor to suck out heat- My monitor gets pretty damn hot- If I had the energy I'd probably stick a 120mm fan in the top of my monitor..


Who knows, that could be it.

Optimummind

I found the culprit--it seems to be high room temp of my room. When I turn the AC on in my room, the monitor shimmering distortion completely goes away even with all of my components overclocked. The question now is, which component is responsible for the shimmering when put under heat? It can't be the CPU because it's being watercooled and never exceeds 36 C.

The remaining possibilities include:

(1) RAM. Currently, both 512MB sticks have Vantec's copper heatsinks attached to them.
(2) Northbridge. I currently have a Swiftech MCX 159-R Copper/Aluminum HSF on it.
(3) Videocard. I have 8 memory copper heatsinks attached & a copper Vantec GPU fan.
(4) My monitor. Maybe the filters are clogged and can't circulate air flow very well.

Let's suppose the problem is my monitor. What can I possibly do to it?? Many circulations I've read all warn about opening up the monitor. They say that currents inside can either give me a nasty shock or kill me even with the power plug unplugged.

Sure, I could turn the AC on whenever it gets distorted but that adds unnecessary noise to my quiet room.

The_Neon_Cowboy

I only breezed over what’s has been said so try not bash me for repeating what has been said but here is my assessment of the situation.

Fans contain magnets; several small magnets close together will constitute a small magnetic field. Also, a lot of current itself can cause RFI. Both, of which can cause the issues you speak of. Etc….. It not just the fans all electronics emit small amounts of EMI
It’s the same effect as how the TV messes up when you run the vacuum cleaner.

#1 I’d Try moving the monitor as far away from your pc, and see you can see it still does it.

#2 you might also try an extra RF choke on your monitor cable as well as some of you other cables (power cables, etc) there about $1.50 @ radio shack

#3 try turning on “spread spectrum” modulation in you bios as it in increases the rage of frequencies your FSB uses to transmit a signal. Using the spectrum you reduce the EMI emitted by your pc by a good deal solves all sorts of issues but results in a slight loss of performance.

#4 make sure you have you case on other wise the room is blasted with EMI and so is the pc.

#5 In theory if you want to see if its something being effected on the monitor end or weather the pc is @ fault wrap your monitor [temporary do not run it this way] with aluminum foil as it will help shield it from a lot of outside EMI

#6 try to keep you cables separated and if they must cross each others path it should be at a true 90 degree angle.

Do you have a digital camera? Some pictures would be Hot! It cold be as simple as having to large of a fan next to you videos card or motherboard. I’d need to see to be of much more help as I can only make shots in the dark about this… But I do believe your issues is being cased by EMI or and outside magnetic field. Inside your monitor is a very specific magnetic field interrupt that field in any way will cause undesirable operation and over time can cause permanent damage!

Optimummind

Thx Neo, for your input. At this point, I have determined that the cause is the monitor overheating. When I maintain my room temperature to 80 F thru AC, the shimmering completely goes away. It stays okay even after I put back all my high-RPM fans.

Optimummind

Today, even with AC maintaining my room temp at 80 C, I got shimmering again...

So, I tried this...I uninstalled my Radeon9800 Pro and took off the Vantec Iceqerq 4 GPU fan. Guess what?? The underside of the HSF wasn't fully contacting the core!! So, instead of using the pins to reconnect the HSF to the core, i used Arctic Silver Alumina thermal adhesive and applied good pressure for about 30 minutes. To speed up the curing process, I even took my hair dryer and blew slow hot air on it for 10 minutes.

I then reinstalled the card and fired up my PC. Even after about 15 minutes, the shimmering hasn't returned yet (crosses my finger ).

I'll have to wait and see whether it comes back later.

Optimummind

Now I think about it, my monitor shimmering problem began around the time I installed the new Catalyst 3.8!! Hmmm...isn't that weird??

Optimummind

I call it the final update cuz I found the problem!! It was my monitor!! I disconnected by 19-in and connected it to my mom's computer and the shimmering appeared on that too.

To make sure it wasn't my PC and its overclock, I connected her monitor to my rig and there is no problem. If there is a problem, it's that her monitor is smaller than mine (17-in vs 19-in).

So, I guess it's time for me to buy a new 19-in monitor. The old 19-in is only 2 years old when that shimmering effect began to appear. I guess that's what you get for buying a cheap, no-name monitor (back then $200 for a 19-in was really cheap). My next purchase is going to be a NEC AccuSync 90 19-in. I did the calculations and after CA tax, the total cost should be $222.57 (without shipping). But, I won't do delivery anyways...only about 30 minute drive.

Logla

I hate monitor failure. I bought a cheapo 19 inch a couple of months ago. I regret it now cos I can't get a decent picture on it. I've already had this thing replaced twice and the 'fault' I have is that the middle of the screen is ever so softly focused and you can see slight grid lines in the bottom right. No end of playing with the focus and moire gets rid of this - it just moves it around the screen. Most annoying. As soon as I can afford it, I'm getting an iiyama screen. Cant wait.

Hope the new display is much better for you mate.