>> 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. 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). 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. RLH -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]