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Greg
05-11-2001, 05:40 PM
My system is a 7600/132, 604e 233mhz processor upgrade, 192 mb ram, 512 L2 cache. The computer will not chime on only on start up. It does chime on restart. I am not sure when the start-up chime stopped, but the computer seems to run fine. I want to do some upgrades, but I do not want to put money into the computer and have it fail. I know the startup chime is a self-test and indicates the basic hardware is okay. To try to solve the problem I have done the following: 1. run Norton Disk Doctor, Apple Disk First Aid and Tech Tools system analyze. All checked okay. The Apple Profiler also reads everything as it is installed. 2. installed two new batteries. 3. initialized the hard drive and reinstalled all applications. 4. removed all ram, vram, cache, daughter card and blew dust out and reinstalled. 5. Tested ram with Newer Technology's Gauges Ram-o-meter and it passed.

The start-up chime was missing before the processor upgrade. I also was using this processor in a 7500/100 without problem.

I will appreciate any input. I do not know where to go next. Thanks. Greg

Louie
05-11-2001, 10:10 PM
That will happen when you have external speakers disabling the internal speaker.

tachyon
05-13-2001, 02:23 AM
have you tried a logic board reset? With the power out, try removing the PRAM battery for over 10 minutes. This zaps your PRAM amongst other things.

Greg
05-14-2001, 09:40 AM
Thanks for the replys. I do not have any external speakers connected and I have left the battery out for 24 hours. The computers clock maintains the correct time also so the battery seems to supply current to proper components. Is their any way to test the logic board myself?

Greg
05-14-2001, 04:18 PM
Okay now I really feel dumb. I do have external speakers. I have a ViewSonic 17GA monitor which has speakers within the cabinet. I connected them so long ago I overlooked them. I unplugged the sound cable to the monitor and I now have the start-up chime back.

The next question would be does having the monitors sound cable connected and no start-up chime cause any trouble with the system? The start-up chime indicates all start up components are okay and the sound cable does interfere with the chime; therefore does the sound cable also interfer with any of the start-up hardware?

Any thoughts?

Louie
05-14-2001, 11:46 PM
I thought so!

The startup chimes sound originates in the bowels of the computer (actually the ROM or PRAM or NVRAM or some dark place like that) and is separate and distinct from the normal sound system. With the external speakers disconnected, you can't regulate the chime volume; ever noticed?

On a cold start, the only way for the chimes to be heard is thru the builtin speaker because the regular sound system is not ready yet (on a restart, it is) and the external speaker plug is muting the internal speaker.

No harm is done. The chimes are still chiming (you hope). You just can't hear them. The chimes are merely a aural diagnostic tool.

Maybe trag knows a way to jury rig the speakers. An extra speaker off the logic board should work.

magician
05-15-2001, 08:32 AM
Louie, I am absolutely prone, prostrating myself and kow-towing in your general direction.

this one made my day.

http://macgurus.com/infopop/emoticons/icon_smile.gif

Greg
05-15-2001, 09:44 AM
Thanks again for your input. I am glad to have this settled.

trag
05-15-2001, 11:31 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Maybe trag knows a way to jury rig the speakers. An extra speaker off the logic board should work.<HR></BLOCKQUOTE>

Well, if he waited a minute between turning on the power to the monitor (with builtin speakers) and starting up the computer, wouldn't the speakers have time to warm up so that the start up sound could play? Unless the amplifier in the monitor is subject to the sleep circuitry which turns the monitor off when it doesn't detect a video signal.

As far as jury rigging, I don't think anything fancy would be worth the trouble. I haven't examined the sound jack, but plugging in the external speakers is either making or breaking a connection between two of the pins on the internal sound jack. If it is breaking a connection, it would be easy enough to connect a couple of wires and a switch to those pins and run it out of the case. Leave the switch closed at start up so the internal speaker will be active. Flip the switch after that, so that your sound circuitry isn't trying to drive too much speaker.

If plugging in the sound jack is closing a connection, any hack would be more complicated and I'd have to think about it for a while.

Greg
05-15-2001, 03:28 PM
Greetings. You're correct. The monitor goes into an energy saving mode within seconds of being powered up. I usually wait for all printers, external drives, etc. to power up before turning on the computer.

As long as I know everything is working as it should I don't think I will mess with adding any switches to the external sound circuit.

Thanks.

Louie
05-15-2001, 05:01 PM
Waiting won't work because the internal speaker has been killed off by the insertion of external speaker plug. You need a second peewee speaker wired so as to not get killed off.

Louie
05-15-2001, 05:05 PM
You could just use a Stickee as a pilot check list. Before every 3rd or 10th cold start, disco the external speakers so you can listen to the chimes. (This is getting silly now).

tachyon
06-12-2001, 11:07 PM
Louie said:
"The startup chimes sound originates in the bowels of the computer (actually the ROM or PRAM or NVRAM or some dark place like that) and is separate and distinct from the normal sound system. With the external speakers disconnected, you can't regulate the chime volume; ever noticed?"

The sound sample is stored in ROM (on pre-new-world Macs). The volume of the chime can be adjusted with the Sound control panel, as these settings are stored in the PRAM. Often here in the workshop we turn a Mac on, hear no chime, think "uh-oh" but then discover the user has muted their sound or dropped the volume level to 0.

Recently I discovered a faulty headphone board can permanently mute an iMac, causing you to think the speakers or logic board has failed; not so! Jeez, what a bitch to replace it, though.