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mpancha · Oct 23, 2007, 11:00 AM

This problem just started with a coworker's G5 tower, basically everything was working fine in the morning, and about a half hour ago we suddenly had red dots covering the entire screen in almost a perfect grid pattern. You can still make out what is on the screen, but its a huge annoyance. This particular coworker is in the graphics department, so needless to say, he can't really do too much work with this problem happening.

So far I've tried the following:

plugged in current monitor to another machine, display is crystal clear, its not the monitor
Plugged in another monitor to the G5 tower, still have red dots everywhere, so problem is the tower
Reset the PRAM, still have the same issue.
Checked display settings, set to highest resolution at millions of colors and 75 hz. I've also tried it at 800x600 with 256 colors at 60 hz, and the problem still exists.

If this were a Windows machine, I'd simply reinstall the display drivers and the problem would be gone, but I can't quite do that on OS X.

computer is a G5 tower, running OS 10.4.10. monitor is an NEC 22" LCD.
any help would be great.

TETENAL · Oct 23, 2007, 11:48 AM

Could be a hardware/graphics card problem.

eggman · Oct 23, 2007, 06:09 PM

It sounds like a classic graphic card problem. I've seen this kind of thing before... it could be in D->A converters, or a problem with video memory itself.

ghporter · Oct 23, 2007, 07:34 PM

I'd be interested to hear if the dots were the same-spacing, size and everything-with different resolutions. While that won't tell you more than "it's the video card", it would tell geeks like me if it was the D-A converters or video RAM... But it really does sound like the video card is no longer playing nice.

mpancha · 11:38 AM

Thanks for the info everyone.

ghporter, I'll fire up the machine and check different resolutions to see if I can eyeball the spacing/size/etc.
ETA: the dots stay in a triangle pattern, similar to a sierpinski triangle (not exactly one, but its the closest phrase I can think of to what I mean) pattern. The triangle pattern stays proportional to the resolution I set (tried 640x480 up to 1024x768, couldn't go higher on the test LCD I'm using as I troubleshoot.

eggman > do you mean classic as in OS 9 classic drivers? On this particular machine, it has never had OS 9 installed. I don't know if that relates to what you were saying though.

Does anyone know where I can find information on what graphic cards are compatible with what Macs? I have a G4 tower at my disposal with an Nvidia GeForce MX (AGP), could I just swap cards and have everything seamlessly integrate without having to reinstall the OS?

Another issue which cropped up today, networking stopped working on this machine on different ports, cables, etc. its not the Network itself, its the networking on this G5 tower.

eggman · Oct 24, 2007, 06:00 PM

Originally Posted by mpancha

eggman > do you mean classic as in OS 9 classic drivers? On this particular machine, it has never had OS 9 installed. I don't know if that relates to what you were saying though.

No, I wasn't referring to OS 9. I was just saying that this was an "instructively typical" symptom of failing display hardware. In a former incarnation, I used to write drivers for video cards, and we'd more than occasionally get a clunker - these being early prototypes, of course - to the point where we'd developed our own slang for describing particular classes of failure.

In your case, we'd say that the video card is "seeing spots".

beez1717 · Oct 24, 2007, 06:47 PM

Let's hoope your video card doesn't go the way of Dave Bowman from 2001 Space Odessy with his last words: "My god! I see stars (or rather "MY GOD I SEE RED SPOTS")"

- - e r i k - - · Oct 24, 2007, 07:22 PM

If you are going to quote a movie, at least get the quote right. It's "My god! It's full of stars!" And wasn't that 2010 anyway?

beez1717 · Oct 24, 2007, 08:59 PM

Originally Posted by - - e r i k - -

If you are going to quote a movie, at least get the quote right. It's "My god! It's full of stars!" And wasn't that 2010 anyway?

Nope, Even though I got the quote wrong, it was in 2001 the Book, AND the movie.

It wasn't even mentioned in 2010!

Art Vandelay · Oct 24, 2007, 09:06 PM

Originally Posted by beez1717

It wasn't even mentioned in 2010!

Yes it was. I never saw 2001 but I have seen 2010 and remember that line vividly.

Art Vandelay · Oct 24, 2007, 09:07 PM

You can try booting from an OS X CD/DVD. If the problem goes away, it's software. If it's still there, it's hardware.

- - e r i k - - · Oct 24, 2007, 09:13 PM

Originally Posted by Art Vandelay

Yes it was. I never saw 2001 but I have seen 2010 and remember that line vividly.

Hey, waddayknow? I am right again:
My God Its Full Of Stars

The famous line "My God, it's full of stars!" were Dave Bowman's final words as he entered the monolith in the book version of 2001: A SpaceOdyssey, in Chapter 39. That line did not occur in the original movie, although it was retrofitted to the various sequels, e.g., in the movie sequel 2010: The Year We Make Contact as being uttered by Dave Bowman as he entered the monolith.

ghporter · Oct 24, 2007, 09:38 PM

Originally Posted by Art Vandelay

Yes it was. I never saw 2001 but I have seen 2010 and remember that line vividly.

It's part of the prologue in 2010. Very definitely.

apollo11 · Oct 27, 2007, 07:02 AM

When Dr. Chandra was talking to SAL about resurrecting HAL in the lab