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Documentation about the Vampire hardware

Does Vampire 2 Need Agnus Present?

Dunbar Moss

Posts 4
01 Oct 2017 15:13


This might sound like a silly question, but, does the Vampire 2 v500 require an Agnus chip to be installed on the Amiga mainboard in order to function?

I have an early Rock Lobster Revision 5 (1987, week 33) that had its Agnus chip removed long ago. Unfortunately, these old mainboards have strange Agnus PLCC sockets: they lack slots for a PLCC removal tool, they don't have any holes in the bottom to allow the Agnus to be pushed out and the Agnus was glued in place with a double sided sticky pad...

Consequently, the socket was broken when the Agnus was removed; So, I can't drop in a replacement chip.

Any advice would be greatly appreciated.


Gunnar von Boehn
(Apollo Team Member)
Posts 6207
01 Oct 2017 15:19


You need AGNUS


Dunbar Moss

Posts 4
01 Oct 2017 15:23


Thank you.

I guess I'll have to get a new mainboard, or solder a new Agnus socket (shudder).


Mallagan Bellator

Posts 393
01 Oct 2017 16:37


Dude, that's such a tragedy :(


Dunbar Moss

Posts 4
01 Oct 2017 17:09


I'm considering paying a professional to fit a new PLCC socket, I don't trust my soldering skills. But, it'll be  shame the board isn't 100% original.

I'm not sure these early mainboards are suitable for Vampires anyway. They won't switch on unless the metal shielding is screwed in place.


Samuel Devulder

Posts 248
01 Oct 2017 18:25


Dunbar Moss wrote:
They won't switch on unless the metal shielding is screwed in place.

Oh! I didn't knew that. What is preventing the amiga to poweron when the shield is absent ?



David Wright

Posts 373
01 Oct 2017 20:41


Never have my shield on.
Found out about Agnus this week when I tried to attach a Megachip.
For one, won’t fit but after reinserting Agnus got an error screen from not being inserted well.


Dunbar Moss

Posts 4
04 Oct 2017 09:51


Samuel Devulder wrote:

  Oh! I didn't knew that. What is preventing the amiga to poweron when the shield is absent ?

I'm no technician, someone else will have to provide you with the details. I've only ever seen it before with old "big box" servers that wouldn't power on with the side panel removed.



Kolbjørn Barmen
(Needs Verification)
Posts 219/ 2
04 Oct 2017 10:02


Dunbar Moss wrote:

  I'm no technician, someone else will have to provide you with the details. I've only ever seen it before with old "big box" servers that wouldn't power on with the side panel removed.

Sound like old Compaq servers, they had a power switch connected to the side panel to prevent people like you from screwing up :)


Samuel Devulder

Posts 248
04 Oct 2017 10:56


Well, that's not the amiga then, but I read that it was the amiga refusing to powerup if the shield is off. Does this mean we are talking about a modified amiga sitting inside a PC-case ? (I find it strange that someone would put his A500 or A600 motherboard inside a PC-case.)


Eric Gus

Posts 477
05 Oct 2017 04:11


Unless there is some real problem with grounding on the motherboard (which is its own distinct issue) .. you do not need the metal shield.. that was just something commodore added to reduce the RF emissions so they could pass the US FCC and ship their products.. And now in this day and age, the main thing it would interfere with is broadcast analog TV .. of which no one uses now..

posts 11