-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I suspect that the gold layer on edge connectors 30-odd years ago was a lot thicker than on modern cards. We are talking contacts on 0.1" spacing not some modern 1/10 of a knat's whisker. (Off topic) I also remember seeing engineers determine which memory chip was at fault and replacing the chip using a soldering iron. Try that on a DIMM! On 19/01/16 00:39, Peter wrote: > On 19/01/16 12:34, J Martin Rushton wrote: >> Not new: I can remember seeing DEC engineers cleaning up the >> contacts on memory boards for a VAX 11/782 with a pencil eraser >> c.1985. It's still a pretty standard first fix to reseat a card >> or connector. > > I used to do that as well. The contacts would come out nice and > shiny when you clean them. Then I found out that what I was > actually doing was removing the very thin layer of gold plating on > the contacts and revealing the copper underneath. That's why you > should never clean contacts with a pencil eraser, just re-seat the > boards and they'll make contact again. > > > Peter _______________________________________________ CentOS > mailing list CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos > -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAEBAgAGBQJWnsboAAoJEAF3yXsqtyBlm3UP/00YVsd3q7lEY1S9fXw/Y5YI uLkfigS6I9/LqVMXL3YT/pmrE745kxROUEfO0qPHDETx2gcjLlq+gOJ1icJMD2sW hn8JY4Pv7IouK4DvZ3hXCIaqQgegsYcqoEi5Ii1F+T+qguS0CHxLqZ98vocPmSnB IOpwId7L5/wgdtsTKgSHcwl2WaEvp2WojOFP7Asv9QbgCxfhpI6AYN3uptjeR0zQ 868Eo5tRoS2g42BijN6PZTc+1HnpFhp/K/Gy/GxzqvBKG+rx/heF4u/xOkCkH78y qbDXVTNcxqr8Uf65302gfGompXPZO56czvMOlxUWcvKU6O2fSlhRfgF1v2XR+7pL jf7E332bSml1W0NlA/fzM9HIXTgX3t+BJ9P0F1wjOLGuXuYf5zvdjXff4yjJlgGC hVc6OEzUZrDM1EAE+Eu8ENqzVg6aTQGm17FkDRuKqVF3XXE4Ok5Pm0+scMjylVRX V0yXKMzRH+T5IUJK6xnFU84Eadr7dl0EUf6f+EX61wDhhUauK3N5XnVNaOZ3dLom fuTjk5Qg+BBHVQPG1/Ud4KK8sEZbB55zc7udinhbh45onn3oUGA4LtoA6wqqgHMJ ue87YC/Y5FPd8G3neei/bVkGrr2EEWgSxJ2PQYxeiXda6trf8nzBNqz7vXK4/mDw fAl4ie58Zd0vGbRAb2hB =iezY -----END PGP SIGNATURE-----