Video RAM causing kernel panics... just use safe mode?

[lamplighter]

My Powerbook G4 12" 1.5 GHz started giving kernel panics at every normal boot (safe boot works fine). After trying all the debug info (PRAM, NVRAM, upgrading to 10.4.10, etc etc) I tried the Apple Hardware Test from my install disc. Everything passed except the Video RAM gave me an "error detected" with error code 2NVD/1/4: 2122.

Everything online is telling me I need a new logic board. However, I can still boot into safe mode. It seems that safe mode just has a few things disabled that I can live without (audio, dvd), especially considering a new logic board will cost me $700. I'm wondering if I can just always use safe mode, or even better, find a way to disable the single item safe mode is disabling that is causing the kernel panic in normal boot.

Any insight on whether this is a brilliant or very stupid idea would be greatly appreciated.

[mad jew]

If Safe Mode is working for you then it could possibly be a driver problem. If everything is backed up, then maybe look at running an Archive & Install, or even a full reformat and reinstall if you're feeling Game (whoever he is).

[lamplighter]

Thanks for the reply mad jew. I'm certainly glad to have another idea to try. I'm not sure how the driver could have a problem as I didn't do a software update directly before the problem, although my hard drive was getting full (I think down to 50 mb left before it warned me) so perhaps something got corrupted there.

If I've been using my Powerbook in safe mode as essentially a TextMate editor over the past few days and it does tend to freeze up after a few hours. Better than buying a new logic board, but also worth trying a reinstall

I guess there is no way to update an individual driver manually?

[mad jew]

Eek! Get more free space. Aim for 8GB free at any one time. Software Update is unrelated to the drivers and an Archive & Install will not work if you have such a small amount of free space. Just clear out some free space and then we'll take things from there.

[lamplighter]

I should've said I did clear to over 2 gigs when I saw that message... anyways, now I'm up to 8 gigs but it looks like I'll need more like 15 gigs to try the Archive & Repair.

Thanks again, even for just giving me some hope

[mad jew]

Haha! An Archive & Install should work with 8GB free though. It merely replaces the System Folder with a new one, and your System Folder shouldn't be over 8GB. Nevertheless, if you can then get to 15GB free, just to give yourself a nice buffer.

[lamplighter]

Just to leave this thread closed in case anyone else has the problem, I tried the Archive & Install with no luck. I then tried formatting and installing. Neither method was able to complete the install, it would reboot and then go to a blue screen with a cursor.

I got a quote from an Apple certified shop and they said it would be $800 CDN for a new logic board (or $1300 if I didn't want to trade in my old one), plus labour. So I went out and bought a Mac Mini for $650 to tide me over until I can afford a new laptop or if I'm lucky find a cheap logic board on eBay and do it myself.

Actually, if anyone wants to sell a Powerbook G4 12" 1.5 ghz logic board let me know

Thanks again for your suggestions mad jew, it is very much appreciated.

[mad jew]

Thanks for posting back lamplighter.

[the CreaTurE]

considering a "driver problem", it's a bit more than that I assume.

the video card will fail as soon as the drivers are loaded. that is not a problem of the drivers (who are fine) but of a broken video card. so a solution without using Safe Mode all the time would be to disable the drivers manually - or buy a video card replacement.

I just described the solution here:

http://forums.macrumors.com/showthre...74#post4458774

[lamplighter]

Woooo!! You are a genius Creature!! Thank you thank you thank you!! I hope anyone with a 2NVD/1/4 Video Ram error will Google this thread and save themselves some time&money... particularly fellow laptop users whose only alternative is a costly logic board upgrade.

I'm not sure why I just noticed your reply this week, but I followed your instructions and my Powerbook is now working (without Core and Quartz video support). Fingers crossed that I won't run into anymore problems, will report back if I do.

In case anyone else gets this error, follow Creature's link above. He basically said:

1. Boot into Safe Mode (hold SHIFT at bootup)
2. Go to /System/Library/Extensions and remove all GeForce* drivers (feel free to back them up somewhere). There were 5 of these files in a vanilla 10.4 install and 6 from a 10.4.11
3. Reboot into normal mode and it should work without Quartz or Core support (you can see this in System Profiler), meaning 3d games and video chat won't work

A few other tidbits I learned on my journey that may be related:

• My optical drive broke at the same time. I made the mistake of forcing in OS X Install Disc 1 (the drive kept spitting it back out, so I forced it in)... then couldn't get it out with any of the usual stuck CD tricks. I ended up sticking a pair of pliers into the middle of the slot and then twisting, to widen the opening. The CD came flying out. (Note: if you rip off the felt, you can see more inside)
• Without an optical drive, I had to put another Mac into target mode with the Install Disc, and hold CTRL on my broken Mac to choose the Install Disc from the good Mac.
• If you are using CDs, after Install Disc 1 it asked me to reboot, but then it would freeze up. I had to hold down SHIFT to go to Safe Mode here, and it brings up the screen asking for Disc 2. You then have to turn the good machine off, boot up normally, switch CDs, and reboot back into target mode. The bad Mac should recognize it.
• If you install an update (I went from 10.4 to 10.4.11), the GeForce driver's will show up again, so you have to remove them again.
• When at vanilla 10.4, both ethernet and Airport wouldn't hold a proper IP, and would actually flood the router with DHCP requests. The solution was to upgrade OS X using the downloadable DMG file from the Apple Support site and using Target mode to transfer the file.

[MacsRgr8]

Originally Posted by lamplighter

Woooo!! You are a genius Creature!! Thank you thank you thank you!! I hope anyone with a 2NVD/1/4 Video Ram error will Google this thread and save themselves some time&money... particularly fellow laptop users whose only alternative is a costly logic board upgrade.

I'm not sure why I just noticed your reply this week, but I followed your instructions and my Powerbook is now working (without Core and Quartz video support). Fingers crossed that I won't run into anymore problems, will report back if I do.

In case anyone else gets this error, follow Creature's link above. He basically said:

1. Boot into Safe Mode (hold SHIFT at bootup)
2. Go to /System/Library/Extensions and remove all GeForce* drivers (feel free to back them up somewhere). There were 5 of these files in a vanilla 10.4 install and 6 from a 10.4.11
3. Reboot into normal mode and it should work without Quartz or Core support (you can see this in System Profiler), meaning 3d games and video chat won't work

So, if I understand correctly, the display works if no grfx acceleration is used....

I mean could it be that disabling the drivers less VRAM is used (in use by normal accelerated Core grfx (core image, quartz extreme), OpenGL libs caching, etc.), and so maybe faulty VRAM hardware is not used, therefore no crash anymore?

[velocityg4]

Well when the drivers are removed all that is left is the IONDRVFramebuffer. I know it allows you to change resolutions and I think it does screen redraws but I do not know what else it does. It could be that using the frame buffer does not use vram at all but uses the CPU to do all screen draws.

Sort of like a fresh install of Windows XP before you install any video drivers.

If you still want to play DVD's try Video LAN client it is uses less resources than Apples DVD playing software. You may be able to get movies to still run if your CPU can handle the extra load.

[belushi81x]

I just wanted to say thank you... I did have a 2nvd error ( mine was 2nvd/1/4:2060 FYI) and this solution gives me a (partial) fix and workaround until I have a chance to replace my old G5 here.


Thank you all and thank google.

[Zerf]

Hello,

I had quite the same problem, and use quite the same method to solve it.

When booting my Apple PowerBook G4 12" (nVidia "GeForce FX Go5200" graphic card), I saw the Apple boot logo (and the spinning wheel) but instead of the login window, I had a black screen (or sometimes vertical strips), and the computer was unusable. I tried hardware verification with "Apple Hardware Test v2.5" (included on Mac OS DVD set), and after at least 10 minutes of test, I had "2NVD/1/4:2122" error. It's pretty easy to work around the problem:

- Boot into single user mode: hold Command+s after power on, until the black text screen
- Remount the hard drive in read/write mode. Type the command:

mount -uw /

- Move one file, with the command:

mv /System/Library/Extensions/NVDAResman.kext /Users

- Enter the command:

reboot

After the reboot, you should see the usual login window. After this trick, you won't be able to control your screen luminosity with the keyboard keys, the power saving settings for the screen doesn't work anymore, video playing (or other accelerated features) are degraded, and screen refresh doesn't work properly (for example, the clock may sometimes be not updated if there is no action on the keyboard or trackpad). However, the computer is usable (as I wrote this message from it).


Regards,
FR

---- Below, the same in french ----

Bonjour,

En démarrant mon PowerBook G4 12 pouces (carte graphique nVidia "GeForce Go5200"), je voyais le logo Apple (et logo tournant), mais au lieu d'obtenir la fenêtre de login, j'avais un écran noir (ou quelques fois des lignes verticales) à la fin du démarrage, et l'ordinateur était inutilisable. J'ai essayé le programme de vérification du matériel "Apple Hardware Test v2.5" (disponible sur les DVD MacOS), et aprés au moins 10 minutes de tests, il m'a indiqué une erreur "2NVD/1/4:2122". La solution pour contourner ce problème est assez simple :

- Démarrer en mode "single" : maintenir les touches Pomme+s enfoncées dès l'allumage, et jusqu'à l'écran noir

(Attention le clavier est en mode américain QWERTY)
- Passer le disque dur en lecture/écriture. Saisir la commande :

mount -uw /

- En cas de difficultés avec le clavier Qwerty, essayer de saisir :

,ount )uz +

- Déplacer un fichier avec la commande :

mv /System/Library/Extensions/NVDAResman.kext /Users

- Redémarrer l'ordinateur avec la commande :

reboot

Après le redémarrage, vous devriez obtenir la fenêtre de login habituelle. Toutefois, après cette modification, il n'est plus possible de régler la luminosite de l'écran avec les touches du clavier, le mode veille de l'écran ne fonctionne plus, les applications utilisant l'accéleration graphique (entre autre les vidéos) sont dégradées, et des problèmes de rafraichissement de l'affichage peuvent survenir (par exemple l'horloge ne s'actualise pas toujours s'il n'y a pas d'actions au clavier ou à la souris). Malgré tout, l'ordinateur reste correctement utilisable (en tout cas bien plus qu'avec un écran noir...).


FR

[q188r]

Thank you Zerf for your solution - helped me out a lot. To show my appreciation I will give you the hope diamond.

[rick001]

All these years later (2012) this work around just saved me BIG TIME. My wife's Powerbook started having Kernel Panics to the point where the computer was unusable. I won't be able to put off buying a computer forever but at least I can wait until AFTER Christmas. Whew!!!

By the way, I copied the Gforce files (6 of them) to a backup folder without using safe mode and then moved them to the Trash, which did require my admin password, and then rebooted. No more Kernel Panics.

Thank you Creature.