I've found some other reports of these freezes scattered about the forums, but usually other people come in and post something about unrelated video cards. So this thread is specific to NVIDIA GeForce GT 130 running OS X Lion (10.7-10.7.3), to avoid confusion and cross-polination of different issues.
Model Name: iMac
Model Identifier: iMac9,1
Processor Name: Intel Core 2 Duo
Processor Speed: 3.06 GHz
Number of Processors: 1
Total Number of Cores: 2
L2 Cache: 6 MB
Memory: 8 GB
Bus Speed: 1.07 GHz
Boot ROM Version: IM91.008D.B08
SMC Version (system): 1.37f3
NVIDIA GeForce GT 130:
Chipset Model: NVIDIA GeForce GT 130
PCIe Lane Width: x16
VRAM (Total): 512 MB
Vendor: NVIDIA (0x10de)
Device ID: 0x062e
Revision ID: 0x00a1
ROM Revision: 3370
Since upgrading to Lion I have had many issues with crashes and kernel panics characterized by the following symptoms, listed here in detail so that people can find them when they search:
- Pixellation - colored pixels appear in different areas of the screen, in seemingly random bunches.
- Mosaics - squares appear redrawn in the wrong part of the screen. Sometimes these squares are large, other times tiny.
- Recovery - sometimes the system recovers once it starts doing these. Other times it just keeps going until it freezes/panics.
- Kernel Panics - I've only had the "grey screen" appear once or twice. Usually there is a complete system lockup before this can happen, and I have to reboot the system manually.
Some solutions/attempts to solve:
- Turn off Energy Saving - This is horrible for the monitor and can lead to burn-in, but I found that many of my crashes occured when the system was trying to recover from "screen sleep". So now I run a screen saver instead, which doesn't seem to trigger it as much.
- Screen Saver - Sometimes I can "refresh" the system by turning on the screen saver and then coming back. Other times, this doesn't work and the pixellation/mosaic remains. Sometimes I can't even initialize the screen saver at all (in which case a total freeze usually occurs right after).
- Rebooting - seems to clear things up for a while, but inevitably, the problem resurfaces.
- Running Windows - Not really a solution, but I have had absolutely no issues with this behavior while running Windows 7 on this same machine (under Bootcamp).
- Downgrading to Snow Leopard - I have not attempted this, but I've read others say that their crashes went away when they did. I would like some more concrete evidence on this if anyone has it.
My diagnosis so far:
- OS X Lion's NVIDIA driver kernel extensions (kexts) seem to be faulty with this GPU. The Windows drivers for this GPU work better on Apple's own hardware than OS X Lion's. Anectodal evidence indicates that Snow Leopard's drivers (at least up to 10.6.3 – more confirmation needed) do not display this issue. I can confirm that this never occurred in Snow Leopard until Lion was released and I upgraded to it.
My request for help and information:
- If you are running this GPU (GeForce GT 130) and OS X Lion, please contribute to this thread offering any solutions you may have or, at the very least, listing your hardware and GPU profile.
- If you can, post crash logs so that we can compare common issues (NVDA Resman seems to be a huge recurring kext in the crash logs, for instance).
- Post screen shots or pictures taken of the pixellation (colored pixels) and mosaic (squares drawn in the wrong place) phenomenon, so we can build a body of evidence regarding this issue. I will continue to update this thread with the same.
I feel Apple has ignored these issues for far too long, and required too many people to simply purchase new computers and new GPUs. If we can build a solid body of evidence regarding this specific issue, it will be a thread that Apple Support can be referred to.