Source: http://www.megalextoria.com/wordpress/index.php/2017/05/10/old-computer-problems-1/
Anybody who collects or uses old computers knows there are a variety of problems you can come across. Heck, even modern computers have some of these issues. Over the years, I think the most common problems I have run across are power supply related. Bad hard drives are pretty common too but those are the easiest to figure out. Bad memory can be a problem but personally, I don't think I have ever run across a problem that was caused by bad memory though there always seems to be a lot of emphasis on that possibility. Then there are the harder problems to figure out...
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One fairly common problem on computers of a certain vintage is bad capacitors. If you open up your computer and you see bulging or leaking capacitors on the motherboard then you know you have a problem. The above picture shows a Pentium 4 motherboard with capacitors that are slightly bulging at the top and leaking slightly. Many times there will only be that slight bulge but this is usually a sign that they are no longer functioning properly and if your computer is behaving badly that is probably why. Usually this only happens on older computers but if your motherboard maker used cheap or faulty capacitors it can start happening in a relatively short amount of time. With the right soldering skills you can replace these capacitors but for most it means it is time for a new motherboard.
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