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skunk
Nov 17, 2006, 09:52 AM
A friend's 20" iMac G4 has been going really slowly of late, so I went over there to try to sort it out. Intending to do an fsck, I restarted with Cms+S: it just restarted as usual. So I thought I'd try zapping the PRAM. Held down Cmd+Opt+P+R, restarted. One "bong" and it went into an ordinary restart. WTF?

Keyboard seems OK, I checked with Keyboard Viewer that the right keys were registering. Is this really odd? Never happened on any of my Macs. :confused:



jeremy.king
Nov 17, 2006, 11:05 AM
what kind of keyboard? Also, you are continuing to hold the key combinations after the chime right? Have you tried others such as boot off CD?

skunk
Nov 17, 2006, 11:31 AM
It's a wired Apple keyboard. Yup, I'm doing the fsck right, I've done it lots of times. Booting off the CD is next on the list.

mad jew
Nov 18, 2006, 12:18 AM
Maybe try using a different keyboard. I can't think why this one isn't being registered at start up. :confused:

iMeowbot
Nov 18, 2006, 12:36 AM
That is what would happen if an Open Firmware password has been set (http://docs.info.apple.com/article.html?artnum=106482).

If your friend doesn't recall having set this, or doesn't recall the password, a reset can still be forced. To force a reset, unscrew the bottom plate and remove the "external" RAM stick, then power up and zap the PRAM.

skunk
Nov 18, 2006, 11:34 AM
That is what would happen if an Open Firmware password has been set (http://docs.info.apple.com/article.html?artnum=106482).

If your friend doesn't recall having set this, or doesn't recall the password, a reset can still be forced. To force a reset, unscrew the bottom plate and remove the "external" RAM stick, then power up and zap the PRAM.I'll probably pass on that one: she wouldn't have a clue about OF.

iMeowbot
Nov 18, 2006, 02:53 PM
I'll probably pass on that one: she wouldn't have a clue about OF.
If the NVRAM has become corrupted, it won't care about that. If keyboards work well except when Open Firmware has control, an Open Firmware problem is well within the realm of possibility.

If you boot up while holding down the option key, you can quickly rule out the password possibility. If a password is set you will be prompted for one. If no password is there, it will proceed straight to the boot volume menu.

If that test passes (the keystroke is understood and no password is present), you can try Apple-Option-O-F so see if it will allow entry to the Open Firmware prompt. If that is successful, the command reset-nvram followed by reset-all should clear any stray settings.

If all those fail to produce results, an NVRAM reset can be forced on a G4 iMac using the PMU reset button (details (http://docs.info.apple.com/article.html?artnum=95165)).

Also, have you brought along another keyboard?

skunk
Nov 18, 2006, 04:25 PM
I shall certainly take one along if nothing else works. Thanks. (She hasn't actually got back to me yet, but I'll tell her to try the OF thang when she does).