MacBook – Why is the Macbook Pro 2011 video garbled after sleep

graphicsmacbook prosleep-wakevideo

Occasionally when I open my new (April 2011) Macbook Pro I'm greeted by an unusable system with a garbled display. Most often I have to force a reboot (hold down power button for 10+ seconds), but occasionally it will fix itself if I close the lid and re-open it.

What is the problem, or what should I look at to find the problem?
Are there other things I could try to wake this laptop from this state?
I can't reliably reproduce the problem, so it doesn't seem that taking it to the genius bar is going to yield useful results, but tell me if I'm making a bad assumption here and I should take it back.

Garbled display output

System info:

MacBookPro8,3
ATI Radeon HD 6750M
Intel HD Graphics 3000
If anything else is relevant, let me know and I'll post it. It's a standard 17" MBP, though I've added memory (notably this problem did occur prior to adding memory as well)

Best Answer

It was bad memory. I had upgraded to 8GB, but at some point suspected the memory for some other problem, so put the original Apple 4GB back in. Both problems went away (tested for 3 months) so I ditched the 8GB and got 16GB of higher quality memory that more closely matched the timing specifications of the original Apple memory.

So far, after two months, I haven't seen this or the other issue yet. So in this case it was bad (or wrong) memory.

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MacBook-Pro Battery – Troubleshooting Automatic Sleep Issues

To help debug sleeping issues, try the pmset command in the terminal:

$ pmset -g assertions

Assertion status system-wide:
   ChargeInhibit                           0
   PreventUserIdleDisplaySleep             0
   PreventUserIdleSystemSleep              1
   NoRealPowerSources_debug                0
   CPUBoundAssertion                       0
   EnableIdleSleep                         1
   PreventSystemSleep                      0
   DisableInflow                           0
   DisableLowPowerBatteryWarnings          0
   ExternalMedia                           0

Listed by owning process:
  pid 2520: [0x0000012c000009d8] PreventUserIdleSystemSleep named: "com.apple.audio.'AppleHDAEngineOutput:1B,0,1,2:0'.noidlesleep"

In this case, it's the process 2520 messing up. Check it out in activity monitor and kill it (/usr/sbin/coreaudiod started by iTunes).

After that, run the command again:

Assertion status system-wide:
   ChargeInhibit                           0
   PreventUserIdleDisplaySleep             0
   PreventUserIdleSystemSleep              0
   NoRealPowerSources_debug                0
   CPUBoundAssertion                       0
   EnableIdleSleep                         1
   PreventSystemSleep                      0
   DisableInflow                           0
   DisableLowPowerBatteryWarnings          0
   ExternalMedia                           0

No flags for PreventUserIdleSystemSleep.

MacBook – Why does the early 2011 MBP hibernate instead of sleep

First, try disabling hibernation (safe sleep) entirely:

sudo pmset -a hibernatemode 0

Then, to remove any trace of other previous hibernations, run:

rm /private/var/vm/sleepimage to free ~4 GB (in my iMac's case)

Should you ever want to turn Safe Sleep back on, run sudo pmset -a hibernatemode 3

If you want to manage all of this with a simple System Preferences pane and it's worth four dollars for you, there's always SmartSleep.

Best Answer

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MacBook-Pro Battery – Troubleshooting Automatic Sleep Issues

MacBook – Why does the early 2011 MBP hibernate instead of sleep

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