where is the computor located on 2002 mazda 626

How long does it take to die? You need to do a parasitic draw test and see if you have excessive amperage drawing when the car is off.

Have you made sure the alternator is putting out even though its new?

alternator puts out 10 volts

Then its not putting out anything battery voltage is 12.6 when fully charged. You should see 13.5 to 14.5 volts at the battery when the vehicle is running if the alt. is working correctly