Hi guys,
I think I might be on the same boat here.
I have a Mac Mini with the following graphics card:
+Chipset Model:NVIDIA GeForce 320M+
Type:GPU
Bus:PCI
+VRAM (Total):128 MB+
+Vendor:NVIDIA (0x10de)+
After 3 months without any problem, I started to meet some completely random freezes where the display would show some weird artifacts.
At first the inputs are still responsive, and after a while everything freezes.
Sometime when I reboot it's back to normal, sometimes the display is still corrupted (usually if I wait a little before rebooting, which could confirm my recent findings).
I first checked the RAM, swapping the sticks, then the disk, then re-installed the system, PMU, SMC, you name it...no luck.
As the crash are pretty random it's hard to tell if the issue is solved or not, and I have to wait and hope for the best.
And yesterday, after 2 months of random crashes, sometimes everyday, sometimes not for a whole week, I found a 100% reproduction method.
I get the same freeze every time I try to import the same 10 videos from my camera, basically copying the files from the camera to the internal HD.
I tried 10 times, deleting and importing the files again, and again and again I got the freeze (between each crash I tried swapping the RAM, etc...)
After checking the crash logs I found those, for every instance of the crash:
+3/14/11 6:52:57 PM kernel NVDA(OpenGL): Channel exception! exception type = 0x8 = Fifo: Watchdog Timeout Error+
+3/14/11 6:52:57 PM kernel 0000006e+
+3/14/11 6:52:57 PM kernel 00000010 00008697 00000474 00000000+
+3/14/11 6:52:57 PM kernel 0000047e 00001528 00000000 0000001b+
+3/14/11 6:52:57 PM kernel 00000000 00000000 01900501+
+3/14/11 6:52:57 PM kernel 00000000 00000000+
+3/14/11 6:52:57 PM kernel NVDA(OpenGL): Channel exception! exception type = 0xd = GR: SW Notify Error+
+3/14/11 6:52:57 PM kernel 0000006e+
+3/14/11 6:52:57 PM kernel 00200000 00008697 00000474 00000010+
+3/14/11 6:52:57 PM kernel 0000047e 00001408 00000001 0000000a+
+3/14/11 6:52:57 PM kernel 00000000 00000000 00000403+
+3/14/11 6:52:57 PM kernel 00000010 00000000+
+3/14/11 6:52:58 PM kernel NVDA(OpenGL): Channel exception! exception type = 0xd = GR: SW Notify Error+
+3/14/11 6:52:58 PM kernel 0000006e+
+3/14/11 6:52:58 PM kernel 00200000 00008697 00000474 00000010+
+3/14/11 6:52:58 PM kernel 0000047e 00001408 00000001 0000000a+
+3/14/11 6:52:58 PM kernel 00000000 00000000 00000413+
+3/14/11 6:52:58 PM kernel 00000010 00000000+
And finally found this thread!!
*Anyway, here is the good news (well sort of):*
Now that I had a 100% reproduction method I was able to test workarounds or fixes.
I first tried to bump up the fan RPM from 1700 to 3000, once the CPU temperature reaches 60°C, after a few seconds the freeze occurs.
Only now, instead of copying successfully 3 files I get 6 before the crash.
I then tried Fan Control and setup a curve to avoid reaching 60°C, and guess what, with a max temperature of 56°C, all 10 files copy without a glitch.
I have only used the Mini for 1 day since the workaround is in place, but no freeze so far.
I am pretty sure the graphics card should not have any problem operating at 60°C.
Now I am not sure what to do, my Mac is still covered by the warranty, but it might be difficult to have Apple admit that there is a problem (even with my logs, and workaround explanation).
On the other hand I am not so thrilled about waiting for the graphics card to deteriorate and die.
Something else I am wondering is, if it's normal for the internal temperature to go from a 40°C to a 60°C in a matter of seconds, just by copying files around?
Anyway sorry for the lengthy post, thought I told my story in case it could help others, any comment or advice is welcome!!
pep.