Mac OS X forum: Freezes requiring hard shutdowns

Hi all,

iMac glass '08 3.06 GHz 500 GHz HD running 10.5.8 with 4G RAM; NVIDIA GeForce 8800 GS graphics card.

My hard drive died last month and I got a new one. Now, I'm having another interesting issue that appears to have something to do with working inside a virtual application for learning and practicing 3D modeling, and it appears to be fairly arbitrary. Sometimes it will run flawlessly. When it does freeze up, everything freezes up. I'm unable to access any other aspect of my computer. I can, however, hear iTunes, or my sister if I'm on Skype at the same time, etc. Those things don't shut down. Force quit was working after a long period of waiting and now is not even coming up. I have to do a hard shutdown.

Last night's permissions repair turned up the following warnings:

Warning: SUID file "System/Library/PrivateFrameworks/DiskManagement.framework/Versions/A/Resources/DiskManagementTool" has been modified and will not be repaired.

Warning: SUID file "System/Library/PrivateFrameworks/DesktopServicesPriv.framework/Versions/A/Resources/Locum" has been modified and will not be repaired.

Warning: SUID file "System/Library/Extensions/webdav_fs.kext/Contents/Resources/load_webdav" has been modified and will not be repaired.

Warning: SUID file "usr/sbin/pppd" has been modified and will not be repaired.

Warning: SUID file "usr/sbin/vpnd" has been modified and will not be repaired.

I have no idea what these relate to, but I'm wondering if this might have something to do with what's going on.

I can run on-board graphics apps with no problem (i.e. Adobe CS4 apps). It's almost like a graphics "freeze."

Thanks.