6100 display issues

[jdlanza]

All:

I have a 6100 that intermittently drives its display on startup.  "Intermittent" means that I get display output about 1 out of every 8 times I start it up.  I'm also noticing that the processor is not hitting the SCSI bus on the times when it does not display.  I get a happy chime, and then nothing.

I  replaced the PRAM battery, but no change.  In fact, the only time I got the display working tonight was by putting in the old, dead, PRAM battery!  I know that battery is dead because the 6100 loses its clock settings.  Only other item of note is that the power supply in the 6100 makes a pretty good amount of moise -- far more than does a sibling 6100 I have right next to it.

Any suggestions?

johnl

 

[Byrd]

Hi John,

6100 are pretty solid machines (short of needing a recap by now), but I'd do the basics first: strip it down to one known good stick of RAM, try another monitor, check video connector/adapter for damage to pins, reseat any cards, RAM etc.

The PSU fans in these often get noisy over time, requiring attention with either compressed air, lubrication or replacement.

JB

 

[Papichulo]

All:

I have a 6100 that intermittently drives its display on startup.  "Intermittent" means that I get display output about 1 out of every 8 times I start it up.  I'm also noticing that the processor is not hitting the SCSI bus on the times when it does not display.  I get a happy chime, and then nothing.

I  replaced the PRAM battery, but no change.  In fact, the only time I got the display working tonight was by putting in the old, dead, PRAM battery!  I know that battery is dead because the 6100 loses its clock settings.  Only other item of note is that the power supply in the 6100 makes a pretty good amount of moise -- far more than does a sibling 6100 I have right next to it.

Any suggestions?

johnl

try turning it on then off and on again

 

[jdlanza]

try turning it on then off and on again

Done that!  Several times!

 

[jdlanza]

Hi John,

6100 are pretty solid machines (short of needing a recap by now), but I'd do the basics first: strip it down to one known good stick of RAM, try another monitor, check video connector/adapter for damage to pins, reseat any cards, RAM etc.

The PSU fans in these often get noisy over time, requiring attention with either compressed air, lubrication or replacement.

JB

Thanks, JB.  Yeah, I'm getting ready to do the whole "tear it down and then build it up" thing.

 

[just.in.time]

Were you able to resolve the 6100 issues?

 

[jdlanza]

Were you able to resolve the 6100 issues?

I did.  It's embarrassing to admit, but I had put the new PRAM battery in backwards.  I don't know, something about the color scheme on tha battery or something.  Funny how it works better when the PRAM battery is in properly!

 

[Daniël]

I did.  It's embarrassing to admit, but I had put the new PRAM battery in backwards.  I don't know, something about the color scheme on tha battery or something.  Funny how it works better when the PRAM battery is in properly!

Yeah, this is one of the handful of Macs that absolutely needs a functioning PRAM battery. Some do for the power-on circuit, but the 6100 is one of the Macs that has internal video that won't work without it installed.

 

[Franklinstein]

Yeah, this is one of the handful of Macs that absolutely needs a functioning PRAM battery. Some do for the power-on circuit, but the 6100 is one of the Macs that has internal video that won't work without it installed.

Truth. Basically any '040 or later hard-power Mac needs a PRAM battery or it won't boot properly, at least not without a quick ON-OFF-ON jump-start. This is because the CUDA needs to be running to properly boot the machine, and without either a PRAM battery or trickle power, it can't be. The jump-start gives the CUDA enough juice to allow it to start operating so that on the next power cycle it can do its job.

Also, try to avoid installing the PRAM battery incorrectly. The CUDA is a CMOS chip and they do not take kindly to being reverse-biased.