Matrox Do Something! (Flickering Part II)

[Livius]

But if the RAMDAC's faulty why does it work so well in 3D and in "still" 2D? I really wish I had an explanation. I am also curious if the problem gets worse and if overclocking the card is more of a risk in these circumstances.

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Celeron PPGA 400 @ 540
Soyo 6BA+ IV, 128MB PC100, G400 16MB SH, SB Live! Value, Quantum FB CX 10.2GB

[noackjr]

(again...)

Just to be sure it is actually the G400's fault, have you tried them in another machine?

Jon

[Haig]

Hi guys,

For those who have this jitter problem, I need the following info:

1 - Serial #

2 - Model #

3 - In what resolution does this happen in?

4 - Once you get into windows, how long does it take before you get this jitter?

5 - If this jitter is instant, do you also get it during bootup?

6 - Does this also happen when nothing in your system is O/C'ed?

Haig

[DarkSyd]

Haig-
I've already got an RMA (just waiting for a good time to be without my G400...) but here's my info anyway:

1- S/N KBL06569

2- Model G4+MA16GB/40

3-Flickering in all resolutions and refresh rates that I have tried

4-I get flickering as soon as I get into Windows

5-I don't see anything noticeable during bootup (nor while accessing BIOS screen)

6-It happens whether the machine is oc'd or not. I've also switched my CPU to a non oc'd PIII500, moved the G400 into my office machine (Cel266 in P2B rev 1.02, not oc'd), and tried in my partner's machine (Cel 366@550 in BP6...also tried at 366). In all cases the flickering was present.

It goes from just noticeable on the Windows desktop to downright annoying when you are running an 3d accelerated app ie. the UT menu screen is just crawling with lines.

Glad to hear your new card is working OK Autopilot.

James

[red2]

Haig-

1-S/N JBF66076

2-Model # can't find it, but it's an early OEM G400 16MB SH

3-All resolutions and refresh rates

4-Jitter is mainly constant but is especially bad after a power on or when the system comes off of standy

5-Have yet to see it during bootup

6-Nothing is O/C

7-Also occurs in BeOS with Mark's driver

It also just started like last month or two after the card was about 6 months old.

[Larry]

Correct me if I'm wrong, guys...

It's not REALLY flickering, but more like a pulsation that sort of makes images on your screen distort ever so lightly. From a distance, it looks a bit like a subtle strobe light...

I have that problem, and it's really weird. I thought my monitor was dying on me, so I bought a new monitor. It wasn't the monitor, so now I can use dual head

Anyway, I noticed that when I moved my system to my house in Toronto, everything is fine. When I move back to London where I go to school, things start flickering again. This indicates that it's not a _total_ hardware problem. In London, I live in a house that is slightly older, with thinner walls, and wiring that is not exactly "state of the art". Anyway, I did a few experiments. My best guess so far is that it had something to do with the current, or more precisely, the quality of the current coming into my house. So, I pack up and move everything to my buddy's place. EVERYTHING WORKS FINE! Okay, so part of it has to do with the current. Perhaps some matrox cards are more picky as to the type of current that the system gets. Perhaps it's not the card at all.

One thing is for sure; I noticed that the problem was far more severe when I was running my desktop at 75Hz as opposed to 85Hz. Also, sometimes, this 'flicker' is better than other times. REALLY wierd. However, what REALLY gave it away for me was the on screen controls for my monitor. Usually, when my monitor changes video modes (standby -> activation / vice versa), it will show a little screen. For the reccord, it's a Vsonic PT775. I noticed that even when my system goes to standby; no signal going to the monitor, the on screen menu display flickers. So, that would lead me to the conclusion that it is not the video card, but my monitor. But both my monitors? First thing that comes to my mind is sheilding, and magnetic fields and stuff. I move everything including my speakers, case, and anything else on my desk away from the monitor, but it still flickered. Finally, I decided to pick up a UPS a with a current and voltage regulator...WOOHOO!!! NO MORE FLICKERING!!!! It turned out to be the inconsistant juice that my monitor was reciving that was making it flicker so much.

Anyway, I'm not trying to say that this the the be-all and end-all of all your flicker problems, but it did help me, so maybe it will help you.

Voltage/current inconsistancies are probably the hardest problems to troubleshoot because the outcome and symptoms are varied and extremely unpredictable. In addition, long term use of computers on powersources that are not consistant can cause unpredictable problems in the system. Lock-ups, program errors, data loss...they all could happen, and they all could happen without any type of "hardware" malfunction. Make sure you have a good power supply, good surge protector, and if need be, a good UPS with a current regulator.

Hope this helps guys...

Larry

[Perception]

where the hell is the serial number? i have model g4+mdha32g

[Haig]

The jitters that you guys are seeing, is this pixel vibration or the entire screen shaking? If you look at the edge of a box, do you see the jitter along the line of the box?

Haig

[DarkSyd]

Haig
Not sure quite what 'pixel vibration' looks like, but I've got a flashing horizontal lines, just a couple of pixels or so wide. They are not always all the way across the screen. They don't stay in the same place. The edge of boxes and windows stays crisp (not wavy or crawly). That's about as clear as I can be without drawing a picture

James

[Livius]

Haig,

First the Symptom Description:
- "Flickering" NEVER happens if the screen is "still" in 2D; it NEVER happens in fullscreen 3D.
- It only happens in 2D if you move something fast (e.g. scroll down quickly through a page) and especially in windowed 3D (but only the rest of the 2D screen, not the 3D window, is corrupted).
- The "flickering" are very thin, black, instantly disappearing horizontal lines. It looks like they were moving up and down the page.
- It happens even with G400 16MB cards that work flawlessly beyond specified speed (150/200) for hours and hours.


1 - s/n JBJ 75586.

2 - Matrox Millennium G400 AGP 16MB.

3 - All resolutions, color depths and refresh rates.

4 - Depends on hat you do. It may or may not appear (see Symptom description).

5 - No.

6 - Yes. It happens with unoverclocked CPU, videocard, and AGP forced to 1x.


7 - Bios 1.5 - 22.

[Livius]

Larry,

what you're describing seems to have nothing to do with what we call flickering - I would not call it jittering, though.



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Celeron PPGA 400 @ 540
Soyo 6BA+ IV, 128MB PC100, G400 16MB SH, SB Live! Value, Quantum FB CX 10.2GB

[red2]

The problem is a jitter. The screen vibrates- moves left and right all the time. After a cold boot or coming off standy the screen shrinks and enlarges real quick for a short while. It is not just along the edges. I tried using the monitor controls to shrink the screen size but it did not help. The problem is getting worse with time. I will be sending in for an RMA as soon as you confirm the problem cannot be fixed at my end.

Before this happened, I used to get the flicker that is described above, wierd lines going across my screen when I scrolled fast. I just thought it was my monitor but now I know differently. I do not get the flicker anymore, just the jitter now.

So if the problem gets worse with time you people should expect to see your screen vibrating shortly.

[MadCat]

Did any of you ever consider that this might not be a hardware problem? I had my Matrox card here at college and it worked fine. Then I went home for break, set up the computer, and bam: jittery picture! It took me all of three weeks to discover that it was an EMF (electro-magnetic field) causing interference. The culprit: an electric motor in the jacuzzi in the adjacent room. All that tightly-wound copper and steel casing produced one powerful EMF even when it was turned off.

First of all, I only got this jitter when my refresh rate was above 60hz and below 100hz, and only in windows. So all of you with complaints, try setting your refresh rate to the highest setting your monitor can manage, and see if the jitters go away (or atleast die down a bit).

You can easily test for electro-magnetic interference. First of all, pack up your setup and move it to another room in your house. Keep it away from obvious EMF sources like televisions, power lines and large appliances. If the problem goes away when you move your stuff, then your problem is likely a powerful EMF. Also, you can detect EMF using a compass. Just walk around your computer's area with the compass. Be sure to keep the compass itself pointed in the same direction at all times. If you see the needle move, youre approaching an electro-magnetic field. If it moves the needle more than 10 degrees, the field is fairly powerful, and can cause all types of interference.

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This Signature Space FOR SALE / RENT

[red2]

I did think it was an EMF too, but since it is isolated to one model of card it would seem to indicate something is defective.

[Autopilot]

Just took another look at this thread. And just wanted to make the comment that the problem that I had is best described by Livius and Darksyd. This <a href="http://forums.murc.ws/ubb/Forum5/HTML/004651.html">thread</a> contains a great deal more info on the problem. Thanks for gathering info on this issue Haig. It's frustrating. My problem is settled, but I keep hoping someone can find a solution to this other than replacement.

[This message has been edited by Autopilot (edited 26 February 2000).]