Flaky A4000

[Bodie]

Hi all,

I recently pulled out the A4000 from the cupboard booted it up and was pleased to see it booted up okay.

However, I have found that after consistent usage it will constantly freeze up. No gurus etc. There is no consistency to the freezing, it can strike any time. The machine has been stripped to the basics (no expansion cards etc). I have tried different ram sticks etc

I have an Apollo 4040 in it - but alas I no longer have the original Commodore board. The Apollo does appear to get very very hot after these crashes.

One thing I did notice when stripping down the A4000 is that it did not have the plastic insulator. Could this be causing it to freeze up constantly??

[paul1981]

Not sure about your freezing issue, but 040's do run hot for sure (which is perfectly normal).
I'm assuming there's no damage around the battery area of the 4000 motherboard due to battery leakage? Any discolouration visible?
If you suspect it could be heat related then I suppose a dodgy solder joint can't be ruled out. Try using a room fan or something to properly blow air on the cpu card and motherboard together - see if it delays the freezing.

Have you had the machine re-capped? There's a chance an invisible leakage could have partially eaten through a track or something (could be under an an smd capacitor you see, leakage hidden). Any sign of dull solder joints on or around any of the smd caps? I suppose all A4000's should be re-capped by now (if the owner is sensible). To me, freezing does sound like CPU card issue.

Good luck, I hope you can get her working soon.

[scuzzb494]

Hi all,

I recently pulled out the A4000 from the cupboard booted it up and was pleased to see it booted up okay.

However, I have found that after consistent usage it will constantly freeze up. No gurus etc. There is no consistency to the freezing, it can strike any time. The machine has been stripped to the basics (no expansion cards etc). I have tried different ram sticks etc

I have an Apollo 4040 in it - but alas I no longer have the original Commodore board. The Apollo does appear to get very very hot after these crashes.

One thing I did notice when stripping down the A4000 is that it did not have the plastic insulator. Could this be causing it to freeze up constantly??

Be very careful messing too much. In truth it could be a very simple thing. With my 4000 all it was was one of the SIM cards not seated properly. Think about how you stored and whether she was left on her side for a while. Likely something is just not seated properly. Gentle steps to start with, I doubt it will be anything that serious, if she was working fine before.

Try leaving the computer running for a while. Also when you say frozen, has the machine frozen, or is just the mouse not working. Dunno. Have you tried running without the hard drive and just using the floppy... tricky cus you probably need the Apollo libraries.

Good luck

[bigmac]

You could try and put a piece of cardboard or plastic between the hard drive bracket and riser card they can short if not insulated this may fix your problem give it a try.
cheers

[mechy]

Hi all,

I recently pulled out the A4000 from the cupboard booted it up and was pleased to see it booted up okay.

However, I have found that after consistent usage it will constantly freeze up. No gurus etc. There is no consistency to the freezing, it can strike any time. The machine has been stripped to the basics (no expansion cards etc). I have tried different ram sticks etc

I have an Apollo 4040 in it - but alas I no longer have the original Commodore board. The Apollo does appear to get very very hot after these crashes.

One thing I did notice when stripping down the A4000 is that it did not have the plastic insulator. Could this be causing it to freeze up constantly??

The mothebroard insulator missing is likely fine, but it sounds like bad contact on the cpu board to the motherboard. Barring that you might suspect software.

is there a fan or heatsink on the 040? there should be.

[tonyvdb]

Heat, have you tried keeping it cooler by placing a fan inside the case moving the air out?
Once it heats up you can get all sorts of issues if it goes above the recommended temps

[Vlabguy1]

Hi all,

I recently pulled out the A4000 from the cupboard booted it up and was pleased to see it booted up okay.

However, I have found that after consistent usage it will constantly freeze up. No gurus etc. There is no consistency to the freezing, it can strike any time. The machine has been stripped to the basics (no expansion cards etc). I have tried different ram sticks etc

I have an Apollo 4040 in it - but alas I no longer have the original Commodore board. The Apollo does appear to get very very hot after these crashes.

One thing I did notice when stripping down the A4000 is that it did not have the plastic insulator. Could this be causing it to freeze up constantly??

Try running the machine without the case, if you think it could be heat related...

[dandelion]

After a childhood drooling over A4000s, I finally got one in mid-2000, but then had similar problems to the ones you are describing - regular lock ups, random resets. I just could never trust it so was never able to use it for important work. I also wasn't keen on how generally chunky and cheap it felt. It put me off Amigas for a while, to be honest. My A1200 was always rock solid though.

[Plaz]

A machine at this age having a thousand solder point could easily have "cold" cracked solder some where. It could show up as a heat related problem as warming the system a bit could cause intermittent connections to open, or cause intermittent low signal conditions.

Also capacitors only have a certain life span. 15 years is typical though I've seen some last 25-30. Unfortunately Commodore didn't use the longest lasting brands.

The power supply will be most sensitive to capacitor aging. It takes the most heat and current. Fluctuating power levels will cause a system to hang do to poor signal levels.

And last the chips themselves can age and die. Their lifespan can depend on the way they were made, amount of heat they radiate, the job they do and the reliability of their power supply. There are systems built in the 70's still going today (think arcades), while many others don't live so long.

If you want to keep that Ami going strong another 20 years. have a pro replace all the capacitors (in the power supply especially) and touch up the solder every where. For the chips you can only say a little prayer, keep them cool and feed with clean power . Replacements  for many are getting tougher to find every year.

PS.... keep your old systems dry! 10-15 years can corrode connections even in a nice environment with average humidity.
I have a few old favorites that don't see the light of day for years. They are double plastic bagged and tied when stored. A couple years ago I pulled out the old SX-64 to play with friends. It worked and looked as good as the day I put it away 12-13 years earlier. Of course it got all the maintenance mentioned above looooong ago before the storage.

Plaz (reparing old stuff since 1984)

[Bodie]

Thank you all for the help.

The good news is, the hangs and crashes are largely gone. Mainly just by improving the cable management and air flow in the case. I have some small cooling parts on order to further maintain the cooling. The a4000 seems to functional well now with an surf and cv64/3D.

The only other issue I now have is a failure to boot at times. I suspect this is down to a faulty chip ram simm, so awaiting on a new one from Amigakit now.

@plaz
Re caps, there appear to be no leaks on the board, however, I have found someone who can do the capping ... And has a repair store just 2km away! Will also get a new PSU or have the caps replaced in the original PSU.

Overall, good to see the a4000 up and running again, thanks all.

[QuikSanz]

recap on all is a good investment. I need to do the same!