[NPMUG] When to reset the PRAM and SMC/PMU

[Sallie Boggs]

I have a time capsule with a ton of gigabites and just got a message  
that it is full and will start omitting the oldest files.  Should i  
disconnect it and start over or what?
On Apr 10, 2009, at 12:37 AM, Dave Sevick wrote:

> Good article from Ted Landau at MacFixit :
>
> http://www.macfixit.com/article.php?story=20090409081833464
>
> ================
> When to reset the PRAM and SMC/PMU
>
> The PRAM
>
> The Parameter RAM is a small amount of "nonvolatile" RAM (NVRAM)  
> that holds various settings that the system can use before the  
> operating system loads, and maintains these settings even when the  
> computer is turned off. There is a small battery on the computer's  
> mainboard that helps maintain the PRAM settings when power is off.
>
> Many times when people's computers get bogged down and they are  
> experiencing problems, advice will be given to "Reset the PRAM." In  
> certain situations this can fix things, but many times people just  
> blindly throw that advice out there. Resetting the PRAM may sound  
> like an exotic fix that somehow may magically cure something;  
> however, many times doing this is just a shot in the dark. As such,  
> it's not necessarily bad for the computer, but may lead to  
> customized settings such as alternate boot devices and speaker  
> volumes being put back at default values. If you have problems with  
> any of the following then a PRAM reset might help you out:
>
> Volume changes or won't stick.
> Video resolutions not sticking or not all available
> Time zone information and clock settings
> Boot volume isn't set (question mark shows briefly before booting)
> Keyboard repeat rates
> Mouse input rates (click and tracking speeds)
> Default system fonts
> Prior to OS X, the PRAM held information for networking, but that  
> has been removed so any network troubles should not be affected by  
> PRAM settings. Sometimes there have been odd problems that have been  
> cured by PRAM resets, including one reported on recently by MacFixIt  
> regarding spell-checking not working. It is possible that settings  
> in the PRAM may indirectly affect various system functions like the  
> spell checker, but knowing this is anyone's guess.
>
> If these settings constantly get reset even when you have not  
> manually reset the PRAM, the computer's logic board battery may need  
> replacing.
>
> To reset the PRAM, reboot the computer and hold the options-command- 
> P-R keys at the same time. The computer will chime, and then  
> continually reset and chime while these keys are held. Allow it to  
> cycle a couple of times and release the keys and allow the computer  
> to boot normally.
>
> NOTE: Resetting the PRAM may require you to set some settings such  
> as mouse speed and keyboard rates again.
>
> The SMC/PMU
>
> The System Management Controller (Intel Macs) or Power Management  
> Unit (PowerPC Macs) is a chip that manages the power for various  
> system components such as the fans and backlights, as well as the  
> circuits that initiates power to the whole system when you turn on  
> your computer.
>
> Like the PRAM, many people readily offer suggestions for resetting  
> the SMC or the PMU. However, there are specific behaviors that will  
> benefit from SMC/PMU resets, and others that won't. For the most  
> part, the power management in the computer should only be reset if  
> you experience problems with seemingly "stuck" settings, or  
> nonfunctional indicators, especially any on the hardware itself  
> (power adapter indicator, or battery life for laptops). The  
> following list of situations are some instances where a SMC/PMU  
> reset can be beneficial:
>
> Battery isn't charging properly
> Display brightness won't work properly
> Keyboard backlight won't work
> Fans blaring all the time
> Power button not functioning properly
> Closing/opening laptop lid doesn't sleep/awaken the computer
> External ports not receiving power
> External devices not recognized
> Internal components such as Airport or Bluetooth not starting up
> Unexpected shutdown
> Resetting the SMC/PMU will depend on the machine you have, but here  
> are some resources for a few Mac models:
>
> Mac Pro
> iMac and Mac Mini
> MacBook and MacBook Pro
>
>
> _______________________________________________
> NPMUG mailing list
> NPMUG at davesevick.com
> http://davesevick.com/mailman/listinfo/npmug

Sallie Boggs Ph. D, DTM
Governor
District 13 Toastmasters
412 731 0724
alotafish at comcast.net





-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://davesevick.com/pipermail/npmug/attachments/20090412/cce26372/attachment.htm