Macintosh SE: Third-Party 80ns SIMMs Can Cause Problems



I'm putting a 2MB RAM upgrade into my Macintosh SE. I started out with
four 120ns 256K SIMMs. I'm putting two 80ns 1MB SIMMs into slots one and
two and am putting the other two 120ns 256K SIMMs into slots three and
four.

At power-on, my screen shows vertical lines spaced evenly across, about 1/4
inch apart. These lines appear right away, even while showing the "happy
Mac" icon. With the lines visible, I can choose "About the Finder" and it
indicates that the Macintosh SE is recognizing all 2.5MB of RAM.

Should I not be mixing 80ns and 120ns SIMMs with a standard Macintosh SE?

We have had reports of third-party 80ns memory having strange effects on
Macintosh SE computers. In all of the cases, the problem was defective
memory modules. The first thing to do is replace the 80ns SIMMs with new
ones. If the problem still continues, try using slower 1MB SIMMs.


Published Date: Feb 18, 2012