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Iamanamma

PRAM won't zap?

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Has anyone ever had this problem?  I just dragged an old G3 out to try to get it running off of a SSD, and I am getting no video from the built-in video or the ATI video card.  Trag suggested I zap the PRAM (which i should have thought of myself).  When I restart with all the correct keys held down, it starts up, but I only get one chime.  I tried replacing the PRAM battery and switching out keyboards.  No luck.  Still no additional chimes.  Is this G3 dead?

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How much RAM does it have?  If it's close to the max of 768MB (I'm assuming this is a beige G3, NOT a blue & white) it may take a while for it to complete the memory check at startup... or it may not come on at all.  Mine are both quirky as hell.  Try powering it on normally, then after you hear the chime, hit command + control + power to force it to restart.  I get video 100% of the time if mine do this.

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15 hours ago, MOS8_030 said:

If you removed the battery then you kinda already did clear the PRAM.

 

Okay.  But it still doesn't explain why I can't get a second chime when I use Option-Command-P-R.

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16 hours ago, Brett B. said:

How much RAM does it have?  If it's close to the max of 768MB (I'm assuming this is a beige G3, NOT a blue & white) it may take a while for it to complete the memory check at startup... or it may not come on at all.  Mine are both quirky as hell.  Try powering it on normally, then after you hear the chime, hit command + control + power to force it to restart.  I get video 100% of the time if mine do this.

You assumed correctly, it's a beige mini-tower.  I can't remember how much RAM is installed, and since I can't get the video to work, I can't tell you how much is installed.   The video decided to work for a couple of hours yesterday, but stopped again after I tried to replace the hard drive with an SSD.  I put all of the original components back in, and I still have problems with it.  Quirky as hell is a good description.  I'm gonna try your trick a couple of times.

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Maybe I'm not reading your procedure correctly, so forgive me if I'm way off base here :)  I've only successfully zapped pRAM by holding down alt+cmd+p+r after the initial start chime: e.g. boot, right after the chime, hold the keys, wait for a second chime—if that's what you're already doing, ignore me :) 

 

Another elementary question here:

Have you had issues with any of the keys? testing it with Key Caps program in Mac OS? Just a thought.

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40 minutes ago, jessenator said:

Maybe I'm not reading your procedure correctly, so forgive me if I'm way off base here :)  I've only successfully zapped pRAM by holding down alt+cmd+p+r after the initial start chime: e.g. boot, right after the chime, hold the keys, wait for a second chime—if that's what you're already doing, ignore me :) 

 

Yes, that's what I am doing.  I don't mind being asked, it makes me take another look and make sure I am doing it correctly.

 

41 minutes ago, jessenator said:

Another elementary question here:

Have you had issues with any of the keys? testing it with Key Caps program in Mac OS? Just a thought.

Don't I need to be able to see something on the monitor to do that?

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10 minutes ago, Iamanamma said:

Don't I need to be able to see something on the monitor to do that?

Ah, I guess if your VGA monitor isn't working that would be tough—sorry if I'm crossing your posts' wires in my head. Did the Rage128 stop working then?

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Are you using a stock Apple keyboard or an aftermarket one?

 

Even though it shouldn't be the case I've had problems with the one aftermarket keyboard I have and commands like that.  Whether it was zapping the PRAM or booting off a different disk for some strange reason that particular keyboard didn't always work reliably when it came to keyboard commands at boot.  The second I'd switch to a stock Apple keyboard everything went off without a hitch.

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1 minute ago, jessenator said:

Ah, I guess if your VGA monitor isn't working that would be tough—sorry if I'm crossing your posts' wires in my head. Did the Rage128 stop working then?

Sorry, I am crossing posts wires.  The reason I was trying to zap the PRAM was because it was suggested to kickstart my video.  Then the PRAM weirdness started.  I have no video.  Period.  Not from the Rage, not from the native.  

 

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Taking the battery out will definitely zap the PRAM—sorry I know that was suggested already.

 

That sounds like there's something deeper going on :/ sorry that's a bit above my pay grade.

 

The battery is good? PSU still in decent shape? Sorry that's the basic stuff I know on these models.

Edited by jessenator
mistakes

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You should be able to zap the PRAM by holding down the key combination either before or after the start up chime.  I've read, but am unceratin, that zapping it before the chime actually resets more parameters.   Pulling the battery and pressing the CUDA switch should reset everything that is stored in NVRAM/PRAM memory.

 

For that matter, you could just try pressing the CUDA switch, IIRC, near the back corner of the board near the third PCI slot.

 

In cases like this, I recommend you remove the PCI video card, leave in the personality card, you need that, but remove the modem card from it, remove all the RAM but one stick, unplug all the hard drive cables, SCSI and IDE.   Don't plug in a keyboard or mouse.    Remove the battery.  With machine unplugged,  hold down the CUDA button for 30 seconds.  Leave the battery out. The Beige doesn't need it to boot.

 

Connect a known working monitor which is capable of 640 X 480 @ 67Hz to the built-in video.   Power up with the power button on the front (back?  can't remember).  If you get a good start up bong, wait a couple of minutes to see if the monitor becomes active.     If not, try a different memory module.   

 

If you can't get a good start up bong or video on the monitor, the problem must be on the motherboard or the monitor.  It's unlikely, though possible, all three memory modules are bad.  

 

If you do get a good start-up screen (gray screen with disk icon and flashing ? mark) start adding components back.  Start with a mouse.  Then keyboard and mouse, etc.

 

All that said, here's another possibility...   The bus speed and CPU multiplier and cache ratio are controlled by a set of jumpers on the motherboard.  Are those still in their original position?  Does the machine still have the original CPU module installed?  Also, you may wish to check the heat sink grease between the CPU and heat sink.   If it's turned to powder, you could have a simple case of the CPU overheating soon after power on.

Edited by trag

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These things seem to need to pass the memory test before a PRAM reset is allowed... Hence why it's not working on the first power cycle before you get video.  That's my suspicion anyway. I'd also try removing and reseating EVERYTHING connected to the logic board except the CPU. Clean the edge connectors on any expansion cards you have installed too. 

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I pulled out a second G3, desktop style this time and it also refuses to work.  It has a nasty problem on the VRM.  Correct me if I am mistaken, but the capacitors appear to be leaking out the bottom?  There is no bulging on the top.

VRM.JPG

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22 hours ago, trag said:

In cases like this, I recommend you remove the PCI video card, leave in the personality card, you need that, but remove the modem card from it,

Couldn't get at one of the screws holding the modem card in place, so I had to leave it there.  It didn't seem to hurt anything, because this:

 

22 hours ago, trag said:

remove all the RAM but one stick, unplug all the hard drive cables, SCSI and IDE.   Don't plug in a keyboard or mouse.    Remove the battery.  With machine unplugged,  hold down the CUDA button for 30 seconds.  Leave the battery out. The Beige doesn't need it to boot.

 

Connect a known working monitor which is capable of 640 X 480 @ 67Hz to the built-in video.   Power up with the power button on the front (back?  can't remember).  If you get a good start up bong, wait a couple of minutes to see if the monitor becomes active.

worked.  BTW, the power button is on the front.  I am going to continue to follow your instructions and see if I can find out what is causing this machine to keep losing its mind on me.

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It looks like there is something wrong with the IDE Ports or cables.  After I plugged the cable into the one that leads to the CD-ROM, the video stopped working again.  I un-plugged it, and the video works again, although it comes up significantly slower.  I have not yet put the Rage video card back in, all that was left was the USB card and the video card, but with the video failing after I re-attached the CD-ROM, I think the  source of the problem is pretty obvious.  I may just switch everything over to the SCSI bus, and use a SCSI2SD board with the largest SD card I can get authorized.  Thank you for everything! 

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Do you know what revision of the ROM that Beige G3 has?

 

The Rev. A ROM did not support Master and Slave devices.   I don't know if having both on the cable would cause such an issue.

 

I can't remember the numbers actively, but would probably recognize which revision they go with.   You can figure the ROM revision by reading the Apple part number off of the two ROM chips  on the ROM module (unless you have one of the rare EEPROM built ones) or by booting up and then using Apple System Profiler to report the ROM revision.   The latter will be something like $77D.45F1.  The former will be 343S0401 or something like that.

 

At a guess, it's more likely there's a problem with the CDROM than that there is a problem with the IDE ports.   Could also be a bad IDE cable.   Oh, check for bent pins on on the connectors.    Sometimes one or more of those gets bent over, instead of going into the appropriate hole, and it gets shorted with a cable is plugged in and pressing against it.

 

Yes, that looks like the caps may be leaking on that VRM.  

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15 hours ago, trag said:

Do you know what revision of the ROM that Beige G3 has?

I didn't know, but since you told me what to do to find out, now I do.  The ROM part number is $77D.45F2.  So it's rev B?  I noticed the CD-ROM is set to master.  It is plugged into its own port on the MB, and is the only device on that cable.  I cannot tell what the HD is set to without researching the drive, it isn't marked on the HD like it is the CD-ROM, but again, it is plugged into a different port, and is the only device on the cable.  I had another SCSI2SD and I slid it into the spare 3.5" bay in the tower, and it let me initialize the virtual hard drives on it.  I may go with it as the new solid state option for that machine, seeing as SCSI does not have size limitations like IDE. I just need to find a honking big capacity SD card. 

Edited by Iamanamma
spelling errors

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It's rev. B or Rev. C.     Which is good.   But with only one device on each cable, it shouldn't matter any way.

 

So, if you plug in either the CDROM drive or the IDE hard drive into either of the IDE ports, the machine does not boot?

 

If that's the case, one last long shot, try a different memory stick.   Why?   It's possible that you have a faulty memory location and that the IDE's driver is always occupying the same location in memory, and that the two happen to correspond.   Like I wrote, it is a long shot.

 

I'm just having trouble accepting that both IDE ports would be bad.    I don't think I've ever seen that in a Beige before.

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35 minutes ago, trag said:

I'm just having trouble accepting that both IDE ports would be bad.

Right now I have the original hard drive running off one of the IDE ports.  I haven't tried switching yet.  I am suspicious that the PSU might be a problem as well.  This is why: I noticed the zip drive wasn't functioning, it's SCSI.  The power cables with p2 (to the HD) and p3 (to the CD-rom) also had a 4 pin power connector on it. I think it's called a floppy style connector.  There was a lovely little open power port that size on the back of the zip drive.  I turned everything off, unplugged the power, plugged the connector into the zip drive, plugged the power cable back in, and powered up the G3.  No love from the zip drive.  So, I powered back down, unplugged the connector, and grabbed the cable with the P5 and p6 connectors on it.  I stuck a spare 4 pin Molex to floppy style connector onto one of them, and reconnected the zip drive to that.  It's all by itself, the only other SCSI device on the bus is a SCSI2SD card, but it gets enough power to run itself from the SCSI cable.  Powered up again, and now there is love from the zip drive.  Now I admit I don't know anything about how the PSU divvies up power between its various cables, but I though it odd that the zip drive would not function unless it was on another cable.

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The Beige G3 can run off of a standard ATX power supply.    There's a jumper on the motherboard to switch it between expecting the Apple PS in the desktop case, or an ATX style supply, which, IIRC, is in the tower case.   Look up the detials somewhere reliable before trying it.   My memory is vague except that the jumper exists.

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On 10/11/2019 at 7:00 PM, trag said:

or an ATX style supply, which, IIRC, is in the tower case.

What I am favoring restoring are our G3 towers.  If I am understanding you correctly, the beige G3 towers have the ATX power supply?  I would be able to find the same thing without excessive amount of difficulty?

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38 minutes ago, Iamanamma said:

What I am favoring restoring are our G3 towers.  If I am understanding you correctly, the beige G3 towers have the ATX power supply?  I would be able to find the same thing without excessive amount of difficulty?

That's what I remember.   You should double check though, because my memory is hazy.

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I just read through a couple articles on the xlr8yourmac site (via archive.org....) that seem to confirm that the beige G3 tower does in fact use an ATX power supply and the motherboard jumper is set to PS/2 power supply... the desktop G3s are set to Mac and have a different PSU.

 

I'd just verify that the ATX PSU of your choice has the correct connectors you're using now - some new ones don't have the older Molex/floppy connectors anymore - and if it does you should be good to go.

 

I saw mention of the voltage regulator - I think the one pictured looks fine, the discoloration appears to be maybe solder flux and not so much leakage.  There was also an issue with these years ago involving Royal brand VRMs that failed and were replaced... yours is a Raytheon so it should be fine, just keep that in mind if you run across one marked Royal.

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