Did my alternator fry my computer?
 

the subject car is my buddys 1984 944 (which used to be mine)

Here's his story:
My alternator bearings took a dump out in the desert, but I decided to drive it as far as I could. All the lights got bright and my battery was apparently over charging.
Finaly the car died. I then replaced the alternator, and all the relays and the coil.
The car cranks and seems to be getting fuel, but it won't start. The radio, turnsignals , emergency flashers won't work either, even after replacing the fuses.

Did I fry the computer?

Probably...

What happened is that your voltage regulator failed, allowing the voltage to cruise at about 18 vdc. That made your headlights brighter, and also boiled out the water from the battery. When enough battery electrolyte was gone, the ability of the battery to mitigate the overvoltage situation was gone, and the voltage on the power circuits jumped from say, 14 vdc to say, 18vdc.

Your dme is the electronic component that can least tolerate the overvoltage condition, and fried.

Of course, the joke is that it fried to save the fuse that was protecting it...

gb