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Do I need to boot into 64bit mode to take advantage of 64bit apps?

The DAW I use just announced 64bit support. My machine is an early 8-core that will not boot into 64bit mode. Is this even necessary though? Will I still be able to access RAM beyond the 4gb cap while booted into 32bit mode?


Thanks!

(2009) 8core 12gb RAM & 2GHz Intel Core i7 MBP 4gb RAM, Mac OS X (10.6.7)

Posted on Jan 23, 2012 8:39 PM

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Posted on Jan 23, 2012 10:18 PM

Is this even necessary though?


No.


Will I still be able to access RAM beyond the 4gb cap while booted into 32bit mode?


Yes.

4 replies

Jan 24, 2012 10:28 AM in response to dan wool

2008 Mac Pro can, it is supported on server OS.

http://support.apple.com/kb/HT3770


Method 1: Startup key combination (for current startup only)

  • If your Mac uses the 32-bit kernel by default, but supports the 64-bit kernel, you can start up using the 64-bit kernel by holding the 6 and 4 keys during startup.
  • If your Mac uses the 64-bit kernel by default, you can start up with the 32-bit kernel by holding the 3 and 2 keys during startup.

Your Mac will revert to the default kernel the next time you reboot it.

Method 2: On-disk setting (persistent)

To select the 64-bit kernel for the current startup disk, use the following command in Terminal:


sudo systemsetup -setkernelbootarchitecture x86_64


http://support.apple.com/kb/HT3773


Early 2008 implemented Unified EFI which is 64-bit but you need to run 10.6.x and even then... so much for "64-bit" hardware and OS talk we heard for years.


http://macperformanceguide.com/SnowLeopard-Compatibility-software.html


Even if you cannot or do not boot the Mac OS X Snow Leopard kernel into 64-bit mode, you can run your 64-bit apps as 64-bit, and they can take advantage of all the memory in the machine. This was/is possible even with Mac OS X 10.5 Leopard. The main problem being that there are only a handful of 64-bit applications available as of September 2009.


http://macperformanceguide.com/SnowLeopard-64bit.html



Somewhere in your "default product" in your profile is where I think the forum pulls that sig

Do I need to boot into 64bit mode to take advantage of 64bit apps?

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