More often than not, kernel panics are hardware based. Specifically, incompatible RAM can cause kernel panics. If you’ve just installed new RAM and you experience a kernel panic, that RAM could be incompatible (or you’ve failed to seat the new RAM properly). In such a case, shut down your Mac, make sure the RAM is firmly inserted, and restart the Mac. If it panics again, remove the new RAM and replace it with the original RAM. If the Mac then behaves normally, contact the RAM dealer for a replacement.
Peripherals and their incompatible drivers can also cause kernel panics. As with gray-screen problems, disconnect peripherals and see if the panic stops occurring. Also update the drivers for your peripherals.
Startup items can also be a problem. Start up your Mac in Safe Boot mode as previously described. If the Mac is panic-free in this mode, choose Apple menu -> System Preferences -> Accounts, and make a note of the items listed in the Login Items tab, as well as their location. To find an item’s location, Control-click (or right-click) on it and choose Reveal In Finder. The location should not only give you an idea of its purpose, but also make it easier to remove that item.
While you can choose to remove all your login items by selecting them and clicking the minus-sign (–) button, start by selecting just those items you don’t think you need (login items for old applications you no longer use, for example). Restart your Mac in the hope that the panics disappear. If not, restart in Safe Boot mode, remove all the login items, and restart. If the panic stops, add back one login item at a time by clicking the plus-sign (+) button. After each addition, restart your Mac and see how it fares. If it panics when you install a particular login item, remove that item, test again, and, if it proves to be the problem, seek out an update to the host application or function or do without it.
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