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Author Topic: A2000 Rev.6 Only 512kb showing up  (Read 2616 times)

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Offline save2600

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Re: A2000 Rev.6 Only 512kb showing up
« on: November 21, 2010, 07:12:45 PM »
do you have the right Agnus chip in there? Even if you do (8372), there may be another jumper that needs to be made. I had the same problem relatively recently on a 2000 refurb. The thread is here, somewhere - but the jumper I am talking about only has its solder pads - NOT a traditional pin and removable jumper scenario. If you don't get this figured out, I'll take a look at my spare A2000 mobo hanging on the wall and identify what solder pads I am talking about and report back. At work now is the thing. In the meantime, if you want to look for yourself - look for some tiny square pads (3 of 'em) near Agnus. If this is the problem, you simply cut the one trace and solder a connection to the other starting from the middle pad. 'Course, I could be totally wrong and getting my mobo revisions mixed up. I see Mechy is on the spot to help save the day...  lmao

Very unlikely you've got bad RAM chips as most of the time, it'll show full RAM available, but yield strange problems as it fills up.
« Last Edit: November 21, 2010, 07:15:56 PM by save2600 »
 

Offline save2600

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Re: A2000 Rev.6 Only 512kb showing up
« Reply #1 on: November 21, 2010, 07:35:34 PM »
That Fast Slot memory card... wasn't that just for use with the really early German made A2000's? Yeah, you're not going to get that puppy configured as Chip RAM I bet, so don't pull your hair out trying. I'd concentrate on seeing what's up with your mobo jumper settings and Agnus version. 8371 and lower revisions only allow 512kb Chip IIRC.

Regarding the Fast Slot memory card... there may be some conflict there too. How does the computer behave with it out? Personally, I'd ditch that thing considering your revision mobo and seek a regular Zorro II Ram solution - they're certainly cheap enough.
« Last Edit: November 21, 2010, 07:38:02 PM by save2600 »
 

Offline save2600

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Re: A2000 Rev.6 Only 512kb showing up
« Reply #2 on: November 21, 2010, 10:59:41 PM »
I swear I had the same problem as you... thought something was broken, but it wasn't. Just needed the correct combination of jumpers settings, as goofy as it may seem (even if it conflicts with what the sites say they should do).  

What happens when you switch J900 by Gary? I can't seem to find any docs that tell us what that's for. J200 is to enable light pens, so no need to bugger with that.

J101, J102 and J500 - I'm thinking you gotta figure out the right combo there and yeah... searching on the site, finally found my A2000 1MB Chip conundrum:

http://www.amiga.org/forums/showthread.php?t=54211
« Last Edit: November 21, 2010, 11:16:48 PM by save2600 »