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DEMinSoCAL

macrumors 603
Original poster
Sep 27, 2005
5,153
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I have a Mac Pro 2009 i'm souping up, and I flashed the 2010 firmware and all that is working, but i'm trying to reset the PRAM so that my RAM is seen as 1333 speed.

Using a wireless Logitech keyboard for Mac, I've tried the COMMAND - OPTION - P - R at the bong and at the grey screen, holding it down but all it does is go to recovery. I've tried a wired USB windows keyboard and hold down WINDOWS - ALT - P - R and same thing. Each and every time it just goes to recovery.

Ideas on how/when to hold and press the key combo or do I really need a wired mac keyboard?
 
If you are on Mavericks or newer, just do "nvram -c" in terminal. That will clear nvram immediately, but you'll probably have to reboot for the memory speed to change.
 
If you are on Mavericks or newer, just do "nvram -c" in terminal. That will clear nvram immediately, but you'll probably have to reboot for the memory speed to change.
I will give it a try. I had found another terminal command "sudo nvram boot-args=-p -r" but that didn't seem to do anything (even after a reboot).

Thank you for the tip.
 
Unfortunately, that did not work. I prefixed the command with "sudo" and entered the admin password, but after a shutdown and restart, my RAM is still at 1066. It's definitely 1333 ECC RAM. I guess I'll have to borrow a wired mac keyboard and try the traditional method.
 
Only install 3 sticks in slot 1-3, and check if the RAM will run in 1333.

It may be not the PRAM's problem.
 
Can you try a different boot arg to make sure that these commands are working on your computer? For example, the following should cause you to boot in verbose mode:
sudo nvram boot-args="-v"
 
FWIW, I borrowed an older white plastic USB Mac keyboard and the CMD - OPT - P - R works like it should.

Seems like wireless keyboards and Windows keyboards just don't work for this.

Once cleared, my RAM is now at 1333.

Thanks all!
 
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Good to know. I thought about getting a BT keyboard but your posts have rejuvenated my affection for my Apple USB wired keyboard. I wish the Apple MagicMouse had a wired version.
 
Good to know. I thought about getting a BT keyboard but your posts have rejuvenated my affection for my Apple USB wired keyboard.

You probably do this type of thing way more often then most, but for me, cordless convenience 99% of the time outweighs corded hassle 100% of the time. I just need to get a cheapo USB wired keyboard to keep around.
 
You probably do this type of thing way more often then most, but for me, cordless convenience 99% of the time outweighs corded hassle 100% of the time. I just need to get a cheapo USB wired keyboard to keep around.

Yeah, I probably do, I test hardware a lot and NVRAM clearing is a normal part of my routine. I actually do have a couple of BT keyboards but not the Apple one. I never use them on my MP, but they are perfect for my iPad use.
 
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