Can't boot into 64-bit mode

[bailorg]

I'm have a 2008 aluminum unibody Macbook with EFI64 (yes, I double-checked)

I just upgraded to 8gb of RAM and I am trying to run Rember to test the memory.

However, in 32-bit kernel mode, Rember returns a "memory lock" error because my system has over 4gb of RAM.

I have tried shutting down and holding 6 and 4 and then pressing the power button, but every time I do this, the system still boots into 32-bit mode.

Is there a proper time to hold down 6 and 4?

Do I press them before or immediately after pressing the power button?

When can I let them go?

Are there drivers or programs starting on login that prevent the system from booting into 64-bit mode?

 

[MarkMS]

Holding the 6 and 4 are the proper keys. Have you tried turning on the machine, then holding the 6 and 4 until the login screen?

Not sure if you've seen this, but this may help. http://macperformanceguide.com/SnowLeopard-64bit.html

 

[Ramasjang]

Hi

I have a late 2008 2GHz macbook also with 8GB ram...

I can't boot into 64bit neither.

Any help out there?

 

[atlanticza]

Hold down the '6' and '4' keys when the Mac starts up (until the Apple log). After starting up in 64-bit mode, check About This Mac…, click More Info, then click on Software. In 64-bit mode there will be a yes next to 64-bit Kernel and Extensions.

If not, see if this helps http://support.apple.com/kb/ht3696

 

[alust2013]

The aluminum MB needs some sort of hack to use 64-bit kernel, and will not work with the default 6 and 4 key startup

 

[bailorg]

The aluminum MB needs some sort of hack to use 64-bit kernel, and will not work with the default 6 and 4 key startup

Is there some reason for this beyond "Apple said so"?