Amiga 1200 tower saga - troubles abound

[blakespot]

So, I've made many posts about my Amiga 1200 tower and the issues it is having. I thought there was a PSU issue. Several. And maybe there were. Likely, but I am not sure at this point.

Things worked fine for a long time, then it started rebooting all the time at startup. Over and over. It has a Blizzard A1260.

Several PSU replacements later, I add the jumper to NOT move ROM it to 32-bit RAM and things boot up. All of a sudden this matters, somehow.

Boots up fine over and over. So I remove the jumper just to see -- doesn't boot -- every 6 seconds I see the 1260 color flash and the power light is blinking the whole time.

So I add it back. System just sits there dark.

So I remove it. Every 6 seconds color flash reboot.

So I add it back. Every 6 second color flash reboot. --- Now same result either state of jumper.

What the hell is going on?

It's getting good power now. Caps are not leaking - shiny solder joints under each, no leakage evident. I have the SCSI adapter for A1260 and two drives on it, been booting from both fine before things went odd.

This thing is driving me crazy. I spent the afternoon watching AGA demos, before I fiddled with this thing. It's sad to see things as they are now.

Ideas? Thanks.




bp

[smerf]

Hi,

@blakespot

Had the same problem with my A1200, found out that you have to use the power from the AT plug on the power supply. By this I mean you have to read out the pins coming off the power supply plug that plugs into the motherboard. If you are trying to use the power from one of the Floppy / Hard drive plugs, not enough power their to support the Blizzard accelerator.

Hopefully this helps.

smerf

[blakespot]

That's covered. No problem there. Using a proper ATX to A1200 power adapter AND have 5v going into the A1200 floppy port. Power is not a problem.



bp

[Djole]

Just one thing, caps will NOT leak, batteries can leak, caps can dry out wich is not visible with a naked eye.

[psxphill]

Just one thing, caps will NOT leak, batteries can leak, caps can dry out wich is not visible with a naked eye.

caps can leak, if the pressure builds up inside and the top gives way then stuff comes out.
 
http://www.maximumpc.com/files/u69/Bad_Caps.jpg
 
http://www.thegeekpub.com/49/how-to-spot-a-leaky-capacitor/

[wurzel]

Try removing all the electronic boards then re-seating them, including the RAM modules.

Possibly some dust has got in & is causing a problem. I had similar troubles to you and that cured mine ...

[amigean]

You say that " I add the jumper to NOT move ROM it to 32-bit RAM and things boot up"...

that had alarm bells ringing for me - sounds like a RAM issue

Try a different ram stick and/or without ram and see if the problem can be reproduced.

Failing that, try an alternative 1200 m/b, they can be had for cheap.

Sorry if that sounds too obvious - but don't know what else to suggest - hope you fix it.

[Ral-Clan]

I agree, sounds like a RAM issue to me too.  But could simply be a bad RAM slot or bad contact.  Obvious thing to do would be to remove all RAM chips/modules and add them back one by one (or pair by pair), testing each time.  Also, try and clean the contacts on the RAM modules (or legs on the chips) and the sockets with alcohol.

Clean every connector inside your Amiga (i.e. power pin connectors, accelerator edge connectors, etc.).