Wierdest Screen Problems I've Ever seen.

[frescies]

WHoa....

I'm at my father's house trying to fix his computer and this is the wierdest thing I've ever seen....

G4 450mhz (agp graphics)
10.2.6
512 RAM
21" Studio display
All peripherals disconnected
PRAM zapped (several times)
Permissions repaired
Disk verified
The only login item is transport monitor

Ok. Computer boots up fine. Display appears fine as computer loads Jag (blue backround and everything appears fine). Then, all of the sudden, a half second after the desktop picture loads, the display appears to freak and suddenly is practically ALL BLACK with little red highlights around what would be the darkest parts of each icon and the text. It's frightening! So... Open up "Displays" in the preferences and the monitor has reverted to 256 color mode but retains all other settings that were there prior to restart. So... Change it to millions of colors and the screen now displays a NEGATIVE desktop (ie where the windows would show white with little blue horizontal lines, it now shows blue with little white horizontal lines), which is much more readable than what happens after login. Now, if I restart, it goes back to the black with red highlights and 256 colors.

Problem with the monitor? Well... It gets better. My father recently installed a second harddrive on this machine, which has a relatively fresh copy of Jag. When I boot off of that volume, it works just fine! I've tried looking for some custom theme altering programs that might be causing the problem but I can't find any (perhaps I'm looking in the wrong place?).

Evidently the computer was working fine until yesterday, then it went to sleep (as usual), and then upon waking it up, the problem started

I'm perplexed!

 

[frescies]

more...

Ok it gets better.....

Loging out makes the monitor normal, until you log back in again. And recalibrating the monitor fails each time

 

[rainman::|:|]

i would start by deleting all of his preferences. It sounds like something specific to his account, my guess would be there. Of course, he will lose all of his settings, but he'll retain all of his data...

pnw

 

[Fukui]

yea, trash his library/preferences folder, log-in and log-out, if not, delete his user, and make another one, and log in as the new user...

 

[frescies]

HAH!

You guys are great!!!.... I made a new user off his account and when I logged into it, the screen was fine! I then went into his preferences in his User/library and looked for something suspicious. I came across com.apple.somethingsomethingsomething"coregraphics"

I deleted the file and now it works just fine!!!

Thanks a ton,
My father will be pleased!

 

[zarathustra]

I can actually tell you how you can replicate this "error". Go to system preferences, go to Universal Access and under "SEEING", turn on "white on black". Now go to your Monitor prefs, and set it to Millions of colors. Is this what you saw?

 

[Nermal]

Originally posted by zarathustra
I can actually tell you how you can replicate this "error". Go to system preferences, go to Universal Access and under "SEEING", turn on "white on black". Now go to your Monitor prefs, and set it to Millions of colors. Is this what you saw?

That's my guess too. That's immediately what I thought when he said it was a negative copy of the desktop.

 

[frescies]

Nope...

Close though.... Thats a true negative. The colors that I saw on his monitor weren't a true negative. They were all over the place, some of them a negative representation. Oddly though, his monitor kept failing to calibrate too. I assume the preference actually was broken, as this happened spontaneously, whilst no one was in system preferences.

Oh man I'd feel stupid of that was the "problem"

REAL STUPID.


Thanks guys

 

[Nermal]

This is not the sort of thing you'd accidentally do, but pressing Ctrl-Option-Command-8 will switch it over to White on Black too.

 

[jimthorn]

Re: Wierdest Screen Problems I've Ever seen.

Originally posted by frescies
Then, all of the sudden, a half second after the desktop picture loads, the display appears to freak and suddenly is practically ALL BLACK with little red highlights around what would be the darkest parts of each icon and the text. It's frightening!

The undocumented "Hell" video mode. It's not a bug, it's a feature.

 

[jzieske]

Re: Re: Wierdest Screen Problems I've Ever seen.

Originally posted by jimthorn
The undocumented "Hell" video mode. It's not a bug, it's a feature.

That is why I paid $129 for Jaguar.

 

[KentuckyApple]

just curious

What (if any) are the practical uses for this "hell mode"?

 

[TEG]

Similar Topic on https://forums.macrumors.com/showthread.php?threadid=31358

I just found out about it, and it seems to use much less power than the normal mode, my battery life is much improved. 4+ v. 3+. It is also great for reading long boring documents, easier on the eyes.

TEG