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-   -   RAM chips for Viper 630 (8mb) (http://eab.abime.net/showthread.php?t=52049)

KONEY 06 April 2010 23:17

RAM chips for Viper 630 (8mb)
 
Hi all,

some of you will for sure remember my posts about Viper configuration and WHDloading crashing.

Since I realized the problems rely on the on-board soldered RAM I decided to change it, and with the occasion fit 4 more MB.

My problem now is to stabilish WHAT CHIPS do I need (must be 32bit ram) and HOW to find them.

A friend of mine advised me to cannibalish some old SIMM modules but this is not so easy as there are many kinds and I'm quite ignorant about the topic.

So, can anybody help me out or give me some hints?

THANX :)

rkauer 07 April 2010 00:12

Those parts are common 1M x 16-Bit Dynamic RAM 1k Refresh with at least 60ns speed. Obsolete now, of course.

You'll find them easily on 4 and 8Mb SIMM sticks and they are in P-SOJ42 package (42-pin chips for SMD soldering).

Part is HYB5118160BSJ-60, but you can grab HYB5118160BSJ-50 (50ns), but the later is rare.

Remember that 3.3V versions exists and are not compatible. I have a few of those SIMM sticks at home, but they will cost too much to send to you.

Here is the PDF datasheet for the unit.

BTW: I can bet your problem is not related to the RAM itself, but to a lack of enough voltage on the accelerator. Check one Vcc memory pin: if the voltage is bellow 4.7V you have some other solutions to try.

KONEY 07 April 2010 00:22

...could be some old cap??

anyway I still want to expand the RAM! so thanx a lot for the data. WIll be checking some old SIMM module and hunt for the component!

rkauer 07 April 2010 00:37

Remember that even installing some RAM chips the board may not "find" them without some slight jumper modification.

About capacitors: did you notice that this accelerator have a floppy-style power connector on the underside?

You need a triple floppy connector (one connector for the Amiga power header, one for for the accelerator and another for the floppy itself). Make a triple connector adaptor and hook it in.

You'll have enough "juice" to power the board then.

rkauer 07 April 2010 00:42

Oh, replacing caps on this little board will not harm it in any way. Go for it.

KONEY 07 April 2010 00:50

well there are only two caps, not a big work :)

About the conncetor...I have two jumpers coming out from one side and no other conncetor.

There is a group of 2+6 holes that COULD be for a conncetor...is that what you're talking about?

rkauer 07 April 2010 01:44

Forgot what I said: the connector is only present on the Apollo 630 (the one with a SIMM socket).

KONEY 07 April 2010 13:19

ah ok! :(

alenppc 03 April 2013 17:12

Sorry for resurrecting this old thread, but I am looking to do the same upgrade, from 4 MB to 8 MB on my Viper 630.

These chips seem very hard to find, compatible ones present on 8 MB simms are all 70ns, while this accelerator requires 60ns at least. EDO SIMMs do have compatible versions at 60ns but will EDO ram work on this accelerator? Especially in conjunction with 2 fast page chips already installed? Can anyone shed some light on this?

Last but not least, please note for those looking to do this upgrade, it will disable the PCMCIA port under Kickstart 3.1, which is a terrible idea on the A600. The designers, in their infinite wisdom chose to map it in the Z-II area despite using a full 68030.

So I will be trying to use a software patch posted in another thread here to bypass this obstacle.

alenppc 22 May 2013 20:49

I soldered an extra 2 ram chips on the board, but the card still only sees 4 MB.

I tried removing them and soldering 2 different ones, no change. So it seems the card's logic is hard-coded to factory shipped amount of ram, and adding chips won't work without reporgramming the logic.

So that's that, then. The card is not really upgradable. :blased

roy bates 22 May 2013 21:14

have you had a look to see if theres any differences between the 4mb version and the 8 mb version other than the memory?

alenppc 22 May 2013 22:50

Not visually, even the 4 mb version has the extra capacitors factory-soldered above the 2 empty chip positions (necessary for the 2 extra chips to work).

Other than that, there don't seem to be any other hardware differences with the exception of logic programming, I suppose.

roy bates 23 May 2013 10:16

a while back i spotted a couple of resistors on the board thats not on the 4mb version i dont know what they do as i dont have one of these.

have a look youll see what i mean as one seems to lead under the pal/gal.

hese 23 May 2013 10:48

@alenppc

You need to solder a 0 Ohm resistor (or a solder bridge) to the empty pads between the 102 and 1002 resistors near the GAL20V8 chip.
That enables the 8 MB.

roy bates 23 May 2013 11:09

Quote:

Originally Posted by hese (Post 890190)
@alenppc

You need to solder a 0 Ohm resistor (or a solder bridge) to the empty pads between the 102 and 1002 resistors near the GAL20V8 chip.
That enables the 8 MB.



thats it:)

alenppc 23 May 2013 15:19

Excellent!! I am gonna try this tonight and report back. Thanks a lot!

alenppc 24 May 2013 00:57

I can confirm that this is indeed the 4/8MB jumper. Now I need to solder back the chips. Making progress... ;)

PR77 18 November 2017 11:30

Just bought an a600 on a gerneral trading website here in Germany and to my absolute surprise the Amiga with a 630 accelerator fitted. Was advertised as a base a600. Anyway any good hints on how to firmly secure the accelerator to the a600 main board and still have the harddisk or CF card attached?


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