Allison: one or both ends. These signals went through the EI cable but timing was critical at best. the later EIs derived cas* and mux* off of ras* inside rather than pipe them over. Generally speaking the mod was one where if it was mostly working it MIGHT help, sometimes it made it worse. There was another mod after that called the buffered EI cable...not a good idea either. Fixing the EI was the solution.<< One of the two units that I have has the mod and the other doesn't. The one without came with the buffered EI cable, so what you said makes sense. Thanks for the info; now I can trace the mod on the new schematics. ------------------------ Rich Cini/WUGNET - ClubWin Charter Member (6) - MCPS Windows 95/Networking