Mac system freezes on startup, but Windows in Bootcamp still runs fine

Question

A few days ago I tried to turn on my Macbook Pro (mid 2010 model, 15 inch)  but it only gave me a black screen and triple beeps. Thanks to this forum I found out it was a RAM problem. So I took it to a local certified mac repair shop and they cleared the RAM issue, but after I entered user name and password on start up, the Mac OS just boots to the desktop and freezes. I can't open any files or folders or apps. Strangely, the Windows in Bootcamp works perfectly--I can open local files and those on the Macintosh disk. The person at the store suggested that it could be a logic board problem or hardware failure. I'm not really buying that since Bootcamp still works (and also I'm reluctant to spend $500).  Anyone has any idea what the issue could be?

Answer 1

You COULD have the bad GPU found in some 15" mid-2010 MacBook Pros... you'd have to take your computer into an Apple Store or an AASP to find out.
Mid-2010 15" MacBook Pros - the bad NVIDIA GPU
If you're having frequent kernel panics with your 15" mid-2010, or intermittent screen problems, the problem is, more than likely, the faulty NVIDIA GPU found in a number of those machines.
Here's just a sample of a kernel panic log that points to the faulty NVIDIA card:
Kernel Extensions in backtrace (with dependencies):
         com.apple.GeForce(6.4.0)@0x82ac4000->0x82b7afff
            dependency: com.apple.NVDAResman(6.4.0)@0x834a0000
            dependency: com.apple.iokit.IONDRVSupport(2.2.1)@0x82fd3000
            dependency: com.apple.iokit.IOPCIFamily(2.6.5)@0x7a802000
            dependency: com.apple.iokit.IOGraphicsFamily(2.2.1)@0x8301b000
         com.apple.nvidia.nv50hal(6.4.0)@0x83c05000->0x84019fff
            dependency: com.apple.NVDAResman(6.4.0)@0x834a0000
         com.apple.NVDAResman(6.4.0)@0x834a0000->0x8378dfff
            dependency: com.apple.iokit.IOPCIFamily(2.6.5)@0x7a802000
            dependency: com.apple.iokit.IONDRVSupport(2.2.1)@0x82fd3000
            dependency: com.apple.iokit.IOGraphicsFamily(2.2.1)@0x8301b000
Here's the "official" Apple take on the issue - but the very real kernel panics need not be preceded by 'Intermittent black screen or loss of video'... in fact, you might not experience any video problems at all. Although video problems can certainly be a portent of things to come…
So what can you do? Print out a copy of your kernel panic and a copy of the Knowledge Base article and take them, along with your machine, to your local Apple Store or an Apple Authorized Service Provider. They should be more than willing to install a new logic board at no cost. I have no idea why this faulty GPU is making the headline here on the MacBook Pro forum so often now - could it be because Mountain Lion is just bringing the issue to a head more readily? I don't know - I only know that we're seeing more and more of these kernel panics of late.
Good luck,
Clinton