Anybody Know This Sad Mac Code?

[CC_333]

Hi,

I am testing some RAM, and I am getting a Sad Mac error code of 03FFFF.

The problem is, I don't know what it means. Obviously there's some bad RAM, but which SIMM or set of SIMMs? The Dead Mac Scrolls doesn't have this error code listed anywhere.

Thanks,

c

 

[unity]

I suspect the RAM is not the issue and instead a bad solder joint. I would very, very closely inspect them all.

 

[unity]

I just read that speed can be an issue. In one case, the RAM was 80ns and replacing with 100ns solved the issue. The 80ns RAM worked fine in another system. Seems weird, but something to look at.

 

[CC_333]

This is a known working board, and with known working RAM, it's fine, so I doubt that there are any bad solder joints (there is a broken clip I discovered, though, but I don't see why that would cause this particular problem).

Sometimes, with the apparently bad RAM installed, the screen will look garbled during the RAM check, then produce the Sad Mac.

I am uncertain how to determine the speed, but I will try to figure it out.

c

 

[unity]

I am uncertain how to determine the speed, but I will try to figure it out.
c

Usually its easy. Look for a -8 or -15 or a solitary number off to the side like "15". 8 or 80 will be 80ns, and so on.

 

[CC_333]

OK, then,

If I'm reading the numbers correctly, I have a set of four 80ns NEC SIMMs and a set of four 70ns Kingston SIMMs.

c

 

[unity]

Which are causing the issue? The faster 70ns or the slower 80ns. And what Mac are these going in?

 

[CC_333]

They both seem to be causing issues, and I'm installing them in a Mac Plus.

As far as I know, faster RAM is fine because it will simply run at the speed of the computer it's installed in. Correct?

So I'm wondering if some of this stuff isn't bad.

c

 

[unity]

As far as I know, faster RAM is fine because it will simply run at the speed of the computer it's installed in. Correct?

Technically. But its not always the case.

Are they two-chip sticks? The Plus can not use those. Also, I am pretty sure they Plus can have RAM installed in pairs, you should not need to put all four in. Someone correct me if I am wrong. And don't forget about the resistor/jumper thingy.

 

[snuci]

Here's onther thread where memory speed appeared to be the issue: viewtopic.php?f=3&t=5708

Switching from 80ns to 100ns memory did the trick.

 

[onlyonemac]

There's also a rather fussy jumper in one corner which has to be set or unset depending on which kind of RAM you're using.

Moral: try changing the jumper before continuing.