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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Gavilan on July 11, 2006, 07:57:38 PM
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Hello guys: i have bought a couple of super agnus 8375 chips, to replace some older chips i have on my machines
I have seen in many places, that they are A500+ and beyond compatibles
So my questions is if this chips are compatible with normal A500, if so what modifications do i have to do to the mobo (if any), and if they are also commpatible with Amiga 600 and Amiga 3000.
Kind Regards
Sebastian
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The short answer is no.
There are different versions of 8375 Agnus for different Amiga revisions and there are different versions for PAL or NTSC.
Not all Agnus chips are electically compatible. Plugging the wrong Agnus in the wrong Amiga will almost certainly destroy your motherboard.
Also if you have any illusions of plugging an 8375 into any Amiga 500 and getting 2-Mbyte Chip RAM you should forget them now.
Putting one in an A500 before the A500+ (assuming it works and doesnt destroy your Amiga) it does not give 2-Mbyte Chip RAM. The most it can give is 1Mbyte and then in some cases only with a motherboard modification. To get 2Mbyte Chip RAM you will need additional hardware.
Tell me:
Exactly which version 8375 you have AND
Exactly which version Agnus you intend to replace AND
Exactly which version Amiga it is for.
and perhaps I can advise.
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A600 doesnt have an Agnus it has Alice.
No it doesn't. Only AGA machines have an Alice.
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The A600 has an 8375 Agnus.
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Yes, my mistake. I was thinking A1200
@Sebastian
If you have a PAL 8375 for A500 (318069-10) I would be interested.
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Thanks a lot for clarifying this confusion i was having
@alexh: i have 5 Super Agnus 8375 lying all over my Amiga stuff. If i find one to be a PAL version, you can have it for free
:-D
Cheers!
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Also, from what I understand, the 8370 was specialized NTSC and 8371 was specialized PAL.
From the 8372 and beyond, the Agnus chips are not specialized for NTSC or PAL, but adapt to whichever machine they are placed in. (This is my understanding -- I haven't imported a PAL machine to test this, though!)
And plugging in a incompatible revision chip probably wouldn't damage anything, though the machine may not boot.
That's not a free reign to go swapping stuff in a mess, though. Plugging in a chip with the wrong orientation would surely fry the chip! Make sure you know where pin 1 is! Also, there is always the risk of ESD or physically damaging the motherboard socket. Chip transplants should always be handled with great care.
Personally, I haven't tried an 8375 on an A500. I did update my 8370 Rev5 A500 to an 8372, which is a normal procedure. I see no reason it wouldn't work with the 8375, though it wouldn't have the additional chip RAM.
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Ilwrath wrote:
Also, from what I understand, the 8370 was specialized NTSC and 8371 was specialized PAL.
From the limited information out there I would agree with you.
From the 8372 and beyond, the Agnus chips are not specialized for NTSC or PAL, but adapt to whichever machine they are placed in.
Not true. It was the case for the 8372 but for the 8375 they went back to NTSC and PAL.
And plugging in a incompatible revision chip probably wouldn't damage anything, though the machine may not boot.
You may be correct, but several posts on Usenet refer to it having a different pinout at at least one refers to a short. Without more information I wouldnt risk it.
The Agnus is the chip with the most revisions and the least information and I tried earlier this year to consolidate the information and dispell a lot of the RUBBISH information about the chips which is re-used over and over.
http://www.amiga.org/forums/showthread.php?t=20895
The full information is FAR from complete but much better than on Amiga-Hardware or anywhere else for that matter.
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Usually I don't go back and revive posts, but in this case, I feel I should.
You may be correct, but several posts on Usenet refer to it having a different pinout at at least one refers to a short. Without more information I wouldnt risk it.
I had never heard of an Agnus with an incompatible pinout. But, upon this new information, I also agree, I would be much more hesitant to try a possibly incompatible version, as well!! So kids.... BE CAREFUL!
Not true. It was the case for the 8372 but for the 8375 they went back to NTSC and PAL.
Really?? I wonder why the heck they did that... I ASSUMED the 8375 would be a unified part, if the 8372 is. MOST companies didn't go around removing cost-saving features like that. :lol:
The Agnus is the chip with the most revisions and the least information
Agreed.
... and I tried earlier this year to consolidate the information and dispell a lot of the RUBBISH information about the chips which is re-used over and over.
Wow... I had missed that post. I must have been on hiatus. Anyhow, that's a great job. I'll see if I have anything that might help shed some light, as well.
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Then why am I sitting on a static flat of NEW chips.
Agnus (2MB) 8375 318069-19 A3000 (NTSC), A3000T (NTSC)