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Putting a Quadra 605 mbo into a LC III

dbraverman88

Well-known member
Hi,

I have a Quadra 605 mbo I would like to put into a working LC III. Could someone please direct me to any available tutorials?

Thanks!

David

 

beachycove

Well-known member
I don't know why you'd need a tutorial, as it's very easy.

Unplug the power connector, the scsi and floppy cables, the fan and speaker wires. Once done, find on each side of the logic board a small piece of plastic or a tab that holds the logic board towards the rear of the machine. There is an angled indent on each side of the logic board that mates with each of those tabs. One will be snug against the power supply, so it might be a good idea to take it out first (it too is just held in by plastic tabs and pulls right out/up once released.)

Push the tabs holding the logic board in place out (gently!), so that you can wiggle the logic board forward. It only needs to come forward 1/4 or 1/2 inch or so. Once moved forward, it will then be free and the swap just involves doing the reverse with the new one and various components. Everything is an exact match, so nothing more is needed than to swap the board.

The only really tricky bit will be avoiding breaking those two little plastic tabs that hold the logic board in place.

 

Maccess

Well-known member
Yep. I've done that. It's a simple motherboard swap.

What you can't do is swap a 475/605 board into an LC case. The locations of the fans and other components are different in an LC.

 

LCGuy

LC Doctor/Hot Rodder
Actually, you can, but you must replace the fan/speaker assembly in the LC with one from an LCII, LCIII or LC475.

 

Maccess

Well-known member
But then you'll also have to craft a location for the fan since half of the original holewill be under the motherboard.

 

SiliconValleyPirate

Well-known member
It's not easily done if you have an Auto-Inject style case with the plastic center Fan/Speaker assy. Howevcer IIRC only one of the grilles is obscured by the later type boards, so maybe you can fix the fan over the speaker grille and put the speaker somewhere else (Note: NOT right up close to the floppy drive!!).

Oh, just incase anyone cares there IS a tutorial for this - I wrote it. It's here:

http://www.68kmac.org/articles.php?id=32

 

dbraverman88

Well-known member
Chris,

I plan to keep the mbo as a backup in case one fries. I have two LC III's and am expecting a third to arrive soon by mail.

David

 
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