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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: krishtov on June 01, 2005, 01:47:41 PM

Title: A500 hardware upgrade
Post by: krishtov on June 01, 2005, 01:47:41 PM

Hello,

I'm a lucky owner of an amiga 500 with rev 6A motherboard.

I think about upgrade it, but I have some questions... :

This motherboard have 4 free slot for memory upgrade to 1 Mo,
I Have 4 chips taken from a PC (the same model than chips in my A590 ), but I don't really know what I have to do, Is there something else to proceed on the motherboard ?

And after the upgrade, will I Use the expansion ram slot ?
(I have read somewhere that I could not).

Title: Re: A500 hardware upgrade
Post by: Noster on June 01, 2005, 01:58:06 PM

Hi,

here is the information you need:

ftp://ftp.uni-paderborn.de///ftp/aminet/pub/hard/hack/500hacks.txt

Noster

Title: Re: A500 hardware upgrade
Post by: krishtov on June 01, 2005, 03:57:37 PM

Thank you for reply,

But I still have a problem, have I to sold a yellow composant on each ram chip ?

Title: Re: A500 hardware upgrade
Post by: Noster on June 02, 2005, 01:59:58 PM

Hi

> have I to sold a yellow composant on each ram chip ?

You mean, if you have to solder a capacitor beneth each ram chip?

I've done it (I've taken the capacitors from the same VGA-card, I've taken the rams from), and it works great (and use sockets for you rams, this way you are safe not to destroy them by heat).

Noster

Title: Re: A500 hardware upgrade
Post by: krishtov on June 02, 2005, 11:23:53 PM

Ok thank you, I feared this answer, because I have found chips on a computer, there are the same as on the board here (http://www.amiga-hardware.com/download_photos/a590_inside_big.jpg)

But when I want to take capacitor, I destroy it... arghhhh ;-)

Title: Re: A500 hardware upgrade
Post by: krishtov on June 05, 2005, 06:27:24 PM

Ok I have succeded on installing memory.
Now I have 1 mo chip memory and 2 mo fast memory.

In addition, I changed my kickstart 1.3 for a kickstart 2.05.

But I cannot plug my 512 expansion card, It don't detect the memory added ...

Is it due to bad operation on JP2 or JP7 ?

Title: Re: A500 hardware upgrade
Post by: Brian on June 05, 2005, 07:56:05 PM

You're fatter Agnus chip can only handle 1Mb of chipmem. The hack mentioned on JP2 and 7 to make the 4 slots on motherboard act as chipmem also makes the memory expansion underneath act as chipmem.

Title: Re: A500 hardware upgrade
Post by: Noster on June 06, 2005, 04:06:49 PM

Hi

> But I cannot plug my 512 expansion card, It don't detect the memory added ..

The added memory on the motherboard and the 512 kb expansion use the same address space, so if you insert the expansion the new memory on the motherboard and the memory on the expansion are accessed both whenever an address in the higher 512 KB chip-ram is addressed. I've heard that there is a hack to enable the 512 kb expansion in conjunction with a 2MB agnus so you will get 1,5 MB chip-ram, but I've never found a description of this hack :-(

I have inserted a defect memory-expansion in the trapdoor-slot -- I've removed the dead ram-chips from this card -- so I still have a battery-backuped clock.

Noster

Title: Re: A500 hardware upgrade
Post by: krishtov on June 06, 2005, 08:07:02 PM

But I have 1 mo Chip Agnus, so it will be impossible I understand ...

Thank you for explanation !!!