Amiga 4000 locks up on reboot

[CountRaven]

Hello Amiga fellows. The time has come to ask about your great help and support for one more time.

If you are boring to read all this... Well the case is that the machine locks up on boot after a hard reboot attempt -power off and on-, it would get back to normal after ten or fifteen minutes.

So,

I have got back my Amiga 4000 today.

The motherboard is fixed, it got a damaged cia chip. Also some upgrades were made, PIO2 upgrade etc. So a new fixed mobo in town.

Everything was put together and back in action. My Cyberstorm PPC, with 128MB of RAM, my Picasso IV -Paloma TV card module included-, my Deneb USB card, a DVDRW and a hard disk, everything powered from a Liteon PSU. The on board RAM is 4MB chip and 16MB Fast Ram on five sticks, 4MB each. Those sticks were not the ones that my mobo used to have, but they were reported working on another 4000.

This configuration was working well in the past.

So, those are the symptoms that make me want to ask for advice.

The machine would boot fine. AmigaOS 3.9, AmigaOS 4.1 on all their victory. MorphoOS PowerUP was not booting, it used to with same configuration. Now this was a no go, actually the machine locked up when trying to boot in this partition, no drive clicks, however I am able to soft reset only to get on the same state. Anyway this is NOT the main problem but read above.

This is the important problem.

I discovered that the same symptoms would be presented when I switch off the machine and reboot. Let me explain. Amiga is off, I would power it on, it would boot and work fine. If I would turn tne machine off and power it on again after some minutes, it would lock up on the Deneb initial screen that appears on boot. Yes. I have tried without Deneb the machine simply locks up, anyway.

HDD light stays on.
No drive activity.
No booting.
There is caps lock on the keyboard and I am able to reset.

And sometimes a green screen on boot and then black screen, or as I said freezing on Deneb's intro screen. If I turn off the machine and turn on again for example on three or five minutes, it is still not booting.. But if I leave it off for a half an hour, or a quarter. It would boot normally.

So,

"Green screen means bad chip RAM", I thought. So I changed the RAM. Pulled out the five sticks of 16MB I was ussing and tried to boot with no RAM at all, thinking the the RAM on Cyberstorm will do the job. No booting. I tried with a single 8mb stick. Machine booted. I think I was using this 8MB stick initially on this Amiga.

Now the MorphOS is booting fine. So that kind explains that this should be a RAM problem. But the same prob remains. After second or third reboot the nachine locks up on boot.

I have put the 8MB stick on the upper chip RAM socket.

The machine reboots perfectly on every soft reset from keyboard.

This PIO2 upgrade mainly improves hard disk speed, trying to test the hard disk behavior copying sn entire partition through AmigaOS 4.1, everything worked well, no crushes. Done that thinking that this upgrade could be the problem. It is actually a chip replacement on mobo.


Do you think is a memory issue?
Is there a way to bypass the on board RAM and use only the Cyberstorm RAM? Yes it is brand new.
Any further thoughts, ideas, advice?.

I will expect your replies.

[Turran]

Do you have the "fix" talked about here? If not, that might be the case why.

http://eab.abime.net/showthread.php?t=64203

[CountRaven]

Wow this seems like a find, I got to check. Thanks.

[CountRaven]

I checked the mobo and it has the fix.

I tried booting with a Workbench 1.3 floppy, managed to do six reboots and then the machine locked up again. This could be a random fact.

Took out Deneb and Picasso, booted on 1.3 floppy with a 1084 on the machine, managed to do two or three reboots, then the lock up.

I was unable to check without the cyberstorm, I have not got another cpu card.

Will try to put the original chips back taking out this pio2 upgrade, please note, those pio2 chips are not getting hot.

Any other ideas?

[Kin Hell]

Maybe you have a failing Hard Drive?

Could be worth running some tests.

[CountRaven]

I sm seriously thinking to put back the original chips, taking out the ones of the PIO2 upgrade...

They can be put out with a tool... Never did something similar... Is there any guide for such task on youtube?

I need to take an idea of the whole thing.

Or perhaps some photos....

Ps. I do nit think this is a hard disk issue, but I can do some tests....

[Kin Hell]

Originally Posted by CountRaven

I sm seriously thinking to put back the original chips, taking out the ones of the PIO2 upgrade...

They can be put out with a tool... Never did something similar... Is there any guide for such task on youtube?

I need to take an idea of the whole thing.

Or perhaps some photos....

Ps. I do nit think this is a hard disk issue, but I can do some tests....

Well bud, replacement CAP's kinda takes a few possibilities out of the equation with these fragile boards. If they guy doing the PIO's did a right job, they should be socketed, but you'll need a suitable PLCC Chip puller for a right job. I've squeezed Buster 9's from Sockets with a Jewellers Screwdriver without cracking the Socket, but on a chip of that small size/depth (same as Buster) use the right tool for the job: - Else they'll split faster than a rotten plum.

Are you running the later C= Drivers for your hardware?

[CountRaven]

Thanks for the info Kin, well I do not think it is a software related issue, I booted with a 1.3 floppy and the symptoms were preety much the same. I mean with no patches etc.... However I can search for a pio2 upgrade version of scsi.device which I have read it exists.

What other kind of drivers could be mobo related?

Ps. It is your ex CyberStorm PPC which runs on this beautiful 4000.

I appreciate your help very much.

[Kin Hell]

The occasional green screen is concerning & would suggest a main-board issue. Tbh, you would be better off having the mobo checked professionally for a right job.

[Loedown]

Random green screens or Gurus suggest there's an intermittent hardware fault. Battery leakage would be the first place to check, including the usual simm sockets that cop a bollocking off a leaky battery. Capacitors also play a heavy part in faults. Remember leakage will happen under components due to surface tension and will indeed be worse under components because of it.

[CountRaven]

Thanks for the answers, problem solved.

I put back the original chips, removing the ones of the PIO2 upgrade. No problem solved.

The mobo is fully recapped.

[Turran]

PIO2 is pretty useless anyway without a very fast CPU =)