Q: Small lines / dots over parts of screen

Does anyone tried to downgrade the system?
Is it possible to change to a former MacOS version?

Hey,
I am having the exact same problem, unfortunately my iMac is out of the mentioned serial numbers,it is W8548........ what should i do? is it insanely expensive to have the card replaced or is it easier to buy a new computer?

hi
this problem happened to our family iMac PowerPC. we got a computer-techy friend to have a look at it and he said the video/graphics card is blown. does anyone know where we can get it fixed in south-east Australia? ill try mac1 and see what they say but as its a few years old i am not expecting a miracle.

Hello Wray Dillard1,

I have the same problems with my chipset *NVIDIA GeForce 7300 GT*

Last Friday fired-up my G5 Imac 20" exact same issue! as below I've tried for a week now to solve this issue. It's fine in safe mode just the cursor has the square of dots I've tried all suggestion posted but nana. I guess apple will be happy as I'm giong to buy another mac but not new this time!
Quote:
My G5 has suddenly developed odd vertical lines and dots in some parts of the screen. For instance following the cursor is a patch of these lines about 15mm square. They're also over any icon and the dock. The desk top is clear but the screen saver is distorted. Dialogue boxes are affected but the field I'm typing into now is crystal clear.

No recent software or updates.

Here's a link to a screen shot which shoes the dock affected but the wall paper not.
http://i141.photobucket.com/albums/r80/OzSTi/Picture2.jpg

Bah! Chalk up another victim.

Photonal,
I'm in Germany and dealing with same issues you had back in April. Any chance you still have that Apple phone number?

Hello! It seems that I may have a similar problem. Could this be the same? Is it a problem with the video RAM?

I have an iMac that I got in 2005 with Mac OS 10.4.11.

A few months ago my desktop started to get weird green and pink lines. They only appear after the computer has been asleep. They seem to always disappear if I open up a game application(Like WarCraft 3) and play for 10 minutes or so. At first when they disappeared I didn't think it was a problem because I could just get rid of them by playing a game, but now I really want to get rid of them for good.

I ran the Apple Hardware Test and it found no problems. But I did notice that while it was testing the video RAM(the screen was going blank/white/blue etc. like the instructions said it would), the green and pink lines appeared for a few moments as well.

Be sure to look here for what the lines look like: http://i12.photobucket.com/albums/a213/FoxSpyFox/Fullscreen_1-3.png

I'm also experiencing the "small dots" problem - dock, menu bar, desktop icons are dotted/fuzzy and photo's become dotted/pixelated when viewed full screen. Most other screens fine - web browser fine for example when using safari and firefox. This started about two months ago. One morning it cleared itself with no apparent intervention but started again in a few hrs. Looking at the rest of the threads it sounds like a logic board issue with no warranty cover.

Then yesterday we played a video through iTunes and it suddenly sorted itself. Its been up and down again since, but stable all day today. The only thing that seems to make a difference is playing videos. I don't understand that at all... does that trigger anything? Do any of you clever people have an idea why that would make a difference? Or does Katy Perry just have healing qualities?

I still don't see any solutions. So I'm chiming in to say, the dance of the dots has started on my screen. My tech said to take a photo, that it might be a 'known problem' but of course, I came home and they'd gone away. Not sure whether to hope they come back or not, but since it's the third time they've appeared, and then for NO APPARENT reason, disappeared, I'm concerned. It also concerns me cause my G4 video went out and I replaced the computer with this one... so MAC.... I hope for better .

SAME PROBLEM. It now appears as if a gray patch (vertical) is also forming. The whole concept of the $$$$$$$ for solving this is ridiculous. My serial # starts with W8

I'm currently having this trouble as well with my G5 (2005).
http://i302.photobucket.com/albums/nn87/kungfou/vramfuck.jpg
Hardware error check gave VRAM error: 2ATI/1/4: 113-xxxxx-117
Apple tech gave it a 'hardware repair-level 1' meaning the replacement of the logic board since video card is integrated.
This does not appear to be a faulty capacitor problem (refer to my screenshot) so similar cases aren't relevant under the particular warranty extension program that finished Dec 2008. My serial number was also just borderline of the serial range of computers eligible for that program (QP525*).
Most windows (e.g., Word, Safari, etc.) aren't affected as of yet. Apple tech said he didn't think it would get any worse, and over the last couple weeks it hasn't.

I am also having this issue, lots of coloured dots on the screen, if started up in normal mode, it works for a few seconds, then the graphics start tearing and it gets a kernel panic. works fine under 'safe boot' (shift at start-up) but with lots of dots/ lines.

Apple hardware test reports a vram error.

When the ambient temp is high (around 30ºC), it seems to work fine, with no dots, glitches or kernel panics, not sure why this is.

My serial number is in the range mentioned in the repair extension program, thus
I suspect a capacitor problem, although I haven't opened it yet to confirm this.

From what I have read this is most likely NOT a vram failure, the problem lies in the capacitors that filter the power going to the graphics card and other components. Anyone experiencing this problem should open their computer and check for bulging / leaking capacitors. some info here: http://www.badcaps.net/pages.php?vid=9.

edit: some more info

So far Does not seem to be an answer here but hoping to find one. I am having variations on the 'theme.' It behaved for a while, then a blob for part of the screen which then formed into the violet lines and after that the little blue points have begun their march across the screen. Sent pix to the technician here in Italy as he said it may be a 'known ' problem in which case hopefully I can get it fixed. But really, as a faithful MAC user I gotta say not GOOD GUYS... my last APPLE crashed video and I bought this one! I'll let you know if I find any answers but pleas do the same. Don't know how to post pix.

Additional thought... question. It all started after connecting a wireless keyboard. Could there be a connection?