On Sat, Mar 08, 2008 at 11:05:34PM -0600, Russell L. Harris wrote: > >> I have a couple of new-to-me old computers. They've been well used > >> in what looks like a normal office environment and they're a bit > >> grimey inside; not just dust that blows away. I figure that I > >> should clean that off so the dust doesn't act like a thermal > >> insulator but I'm unsure what to use, since air alone isn't doing > >> it. I don't want to remove e.g. the CPU from its socket. (P-133, > >> socket 7). > > You need to remove all socketed devices, and especially the CPU. > > Cleaning presents a danger to the aluminum electrolytic capacitors. > Some chemicals quickly penetrate the seals and ruin the capacitors.
Yeah, that's my concern. Boards are usually cleaned of flux after the soldering with circuit-board cleaner, which presumably is safe for the newly-soldered caps. I'll look, but I think that the only socketed devices are the two CPUs. I do have heat-grease. > A mild concentration of dish detergent (not alkaline dishwasher > detergent) in water and a toothbrush, followed by a hair dryer (but be > careful not to get the electrolytic capacitors too warm! -- they can > burst!) likely is the safest approach. > > I think that the use of alcohol might be a mistake. At best, alcohol > would help get rid of water held by capillary action in the sockets, > but warming the board with a hair dryer accomplishes that. > > If you have an instrument service shop in your town, phone or visit > and ask the technician what he uses. Some do use a dishwasher, but I > do not know what detergent is safe for the electrolytics (as well as > safe for the pump seals of the dishwasher). I haven't seen any service shops around here. The attitude seems to be swap and replace defective parts rather than cleaning and repairing. A computer more than 6 months old is considered "old". > Years ago, you could purchase a gallon can of Freon-TF, which I > believe was safe for aluminum electrolytics; with Freon-TF, you simply > put the motherboard in a shallow pan and rinse or soak the board. Since my main concern is keeping the chips cool (including the CPU coolers), I may worry about surface-cleaning those with e.g. damp Q-tip and not try to soak the board and risk the caps. Thanks, Doug. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
