Memory expansion for A500 + ACA500

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DonutKing

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I am looking for a memory expansion for my Amiga 500. It is a rev 6a with 512kb trapdoor and an ACA500. Otherwise it is totally stock.

I'm testing the waters to see if there is something a little cheaper than a new ACA1220. (y)

I will need postage to Australia as well.
 
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Well, only ACAs and Blizzards will work, so it should be a bit difficult to find something cheaper than an ACA-1220...
 
I don't necessarily mean an expansion for the A1200 slot, maybe something like a MiniMegiChip or a fastRAM expansion that attaches to the Gary chip.
 
if its fastram you want you have to go for something on the sidecar slot or cpu socket.
 
if its fastram you want you have to go for something on the sidecar slot or cpu socket.

Not compatible with the aca500
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Afaik this is the only way to add memory to an a500 +aca500 without adding an aca12xx
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honestly,in my opinion,just get a low end aca 1200 card and use that with the aca500.

if you want more"chipram" you will have to go via the trapdoor or agnus socket.
 
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Yep, after reading these comments and looking at sold items here and on ebay, it seems that the 16MHz ACA1220 is the most cost effective option...


that ebay link that fitzsteve posted was exactly the sort of thing I was thinking of... but when you think about it, you're only getting an extra 1.5MB RAM, still not enough to comfortably run all whdload games with preload.

I'm finding quite a few games won't launch, complaining that they can't allocate expmem or shadowmem.

I tried putting in a 3.1 kickstart ROM and disabling maprom on the ACA500 to free up half a meg but its still not quite enough.

I could get that expansion on ebay and see how it goes but I daresay there will still be things that complain about lack of memory... or I could just pay a little more than half again, get a new ACA1220 with a warranty, and more RAM than I would ever need.

So I think I will just bite the bullet and grab an ACA1220.
It costs a little more but the warranty, cpu and large amount of RAM really do make it seem like the most cost effective option.
 
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The ACA12xx will really transform the A500, it's a serious boost over using the ACA500 in stock form.

There are still some games/applications that need more than 1mb Chip Ram but for a full 2mb chip Ram you will need an expansion like the MiniMegiChip and they do carry a cost premium, Hikey was selling some on here the other day (or something similar)

Are you going to buy the ACA new or shall we leave the thread open in case you get offered a used board?
 
Ive ordered one now so this can be closed :)

Hopefully chipram wont be much of a problem, but if it is, upgrading to an A1200 mighr be a better deal than forking over for a chipram expansion.... but at least I can keep the ACA1220 :)
 
I've ended up forking out for an ACA1232-25. However after a months or so of using it, I'm disappointed with the performance.

Sure, workbench generally runs MUCH faster, however most games/demos that make heavy use of the custom chipset actually run slower with the ACA1232 than with the ACA500 or even with no expansion at all.

This is clearly evident in a number of games and demos, whdload or otherwise. For example, Zool, James Pond, Spaceballs-Spasmolytic demo, all get slow downs, stutters and zool even gets video tearing. No amount of fiddling with whdload config or tooltypes has fixed it. If I make a floppy of the game/demo and boot off it I get the same slowdowns so I know its not related to whdload blitter patches. However, if I disable the ACA1232 using the disable-jumper, everything works fine.

I ran bustest and the WHDLOAD memory speed slave (in the dev package under /src) and I found that chip bandwidth actually seems to reduce when the ACA1232 is enabled. I can only assume that whatever the ACA500 is doing to make the A1200 accelerator work incurs some performance penalty when accessing the amiga chipset.

I'm finding more and more often that I'm disabling the ACA1232 to make things run properly. So I am thinking I will go back to my original plan to get some A500 memory expansions and sell the ACA1232.

So, I am again looking for a trapdoor exansion with ~1.8MB and a Gary adapter, or any other RAM expansion that works with the ACA500. I see fitzsteve has a 'GTI-edition 68k-fastram' 2MB expansion, that clips under the 68000 CPU on the motherboard but is confirmed working with the ACA500, so ideally I want something like that.
 
Hi mate, I've picked up an ACA1230/56 for my A500+ so might be tempted to let my 2mb ram board go at some point. I need to test more stuff, as you say performance is epic but I'm noticing some glitches.

These weren't evident with my ACA1232 though.
 
I'd be keen to buys yours if you do sell it.


If you get bored one day, would you mind testing some of those games/demos I've mentioned? Try with and without the ACA1230 and see if you notice any difference in performance.
I'd be interested to confirm this is actually a problem with the ACA500's accelerator port and not just something screwy on my machine. Given commodore's reputation for quality control I guess anything is possible.

Zool was choppy pretty much all the time, James Pond was choppy with 2/3 of those shark enemies on the screen in the first level. Even turrican seems to slow down more with the ACA1232 enabled than without it.

Spaceballs-spasmolytic was slowing down at 0:33 and 2:21 of this video http://www.youtube.com/watch?v=FpcUSAzH82k This occurs on both the whdload version and the ADF.
'Vision Factory - Violation 87' is a quick and easy one - when you pick a demo from the menu there is a text zoom effect, this effect and the music will slow down with the ACA1232.


Thanks :)
 
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