Boot Your Mac to 64-Bit Automatically
Apple made two decisions when launching Snow Leopard this fall. One was to make the entire kernel 64-bit, and the other was to have it default boot to 32-bit mode. I’m not quite sure why they did this, especially with their new line of macs having at least 4GB and in some cases up to 16GB. I always want my machine booting to 64-bit so I can take advantage of the extra memory and because I’m starting to use more and more 64-bit applications.
There has been the much documented solution to hold the “6″ and “4″ buttons down at boot-up, but since I reboot quite often and turn my machines off at night, I’d like an automatic solution. The best solution I found after doing a lot of Googling around was to edit a small file found in
/Library/Preferences/SystemConfiguration/
In this folder look for the file named
com.apple.Boot.plist
Edit this file in a programming editor such as TextMate or Script Editor. The file by default should look like the following:
<plist version="1.0"> <dict> <key>Kernel</key> <string>mach_kernel</string> <key>Kernel Flags</key> <string></string> </dict> </plist>
Change the 6th line to the following new entry so it appear as follows:
<plist version="1.0"> <dict> <key>Kernel</key> <string>mach_kernel</string> <key>Kernel Flags</key> <string>arch=x86_64</string> </dict> </plist>
Now you can reboot you Mac and it will automatically boot into 64-bit mode. If you have a better or different solution to this please post it in the comments.