Its not so much the age of the system more how long it is since it last ran. As minimum isolate the positive terminal and put a meter on ohms range across it. As the capacitor charges the resistance will rise. If it does then good if not or goes up slowly then change the capacitor. I rang our old (now retired) DEC branch field service manager and he said "Turn on a 750 stored for years and with no load on the PSU .. Sure use a pole about twenty feet long!!" Rod -----Original Message----- From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org] On Behalf Of Patrick Finnegan Sent: 08 October 2007 19:29 To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: VAX 11/750 rescued, alas... On Sunday 07 October 2007, Rod Smallwood wrote: 11/750s aren't that old (early 80s), and shouldn't need reforming. It appears that William Donzelli agrees with me, and I'm sure he has more experience with this than I do. Pat -- Purdue University Research Computing --- http://www.rcac.purdue.edu/ The Computer Refuge --- http://computer-refuge.org