NOTE: You should no longer trust your original 35-40 year old power supply. There are several factors for this, and all are explained in detail in our Wiki page. In short – you chances of experiencing intermittent issues and crashing is greatly increased. The correct action is to fully rebuild your power supply, however this takes hours of time and the correct parts can be hard to find – assuming you have the knowledge to correctly select current replacements. And we HIGHLY recommend getting your rebuilt unit calibrated or certified by a company with the correct testing tools and experience which also costs more than a new Universal PSU Kit.