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I just got a new Macbook Pro. I know it's an Intel processor, but is it 32 bits or 64 bits processor?

share|improve this question It's highly unlikely that any mainstream desktop processors from Intel will not support 64-bit in the future. – Steve Folly Apr 15 '10 at 22:25
up vote 10 down vote accepted

64bit processor

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Enter this into Terminal:

uname -a

If you see


at the end of the string returned , your OS X kernel suports 64 bit.

Also bear in mind you need to hold down the 6 and 4 keys while booting to startup with the 64 bit kernel ( there are other ways to accomplish this as well )

At least this was the case on recent Macs - I assume the new MacBook Pros released in April 2010 still boot by default into 32 bit mode as well.

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A 32-bit kernel doesn't prevent apps running in 64-bit mode - just look at Activity Monitor. – Steve Folly Apr 15 '10 at 22:16
And in any case, even if the kernel is 32-bit, the processor can still be (and indeed, is) capable of 64-bit. – Steve Folly Apr 15 '10 at 22:18
I don't see x86_64... this is mine: Darwin Michael-Changs-MacBook-Pro.local 10.3.1 Darwin Kernel Version 10.3.1: Mon Mar 22 15:13:15 PDT 2010; root:xnu-1504.3.52~1/RELEASE_I386 i386 what does that mean? – SIr Codealot Apr 16 '10 at 16:43
Hi Mike .. if you've seeing I386 ...then your MacBook is booted into the 32 bit kernel. – CaseyIT Apr 16 '10 at 16:56

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