Q: When we lost our Internet connection, we took our 2006 Dell Dimension E510 PC to two repair shops. Both said the PC's main circuit board had to be replaced because it had a single "blown" capacitor that had controlled the Internet connection. I hate to lose a PC because of one capacitor. Is there a workaround?
Wyn Coates, Covington, La.
A: No, the repair shops are correct. The loss of a capacitor worth about a dollar has rendered your PC's main circuit board worthless. Why? Main circuit board components can't be serviced individually unless you're an expert with special equipment.
What would cause this to happen? Capacitors are designed to store small amounts of electrical charge. If your PC had encountered a power surge from an electrical outlet, multiple capacitors on the circuit board would have been destroyed. The fact that only one failed means that particular component was flawed.
You could buy a replacement main circuit board (also called a motherboard) for $100 to $120 plus shipping (see tinyurl.com/la3msbf or tinyurl.com/jwhzzgm). But because your $700 PC is nine years old, you'd be better off to buy a new Windows 7 PC for as little as $350.
Q: My Windows 8 laptop can't install Windows updates. Instead, I get the error message "Failure configuring Windows updates. Reverting changes. Do not turn off your computer." This takes half an hour. I've tried everything but a "clean boot" of Windows. Any suggestions?
Richard Baldwin, Perth, Australia
A: A non-Microsoft program probably is interfering with the installation of Windows updates. The Windows "clean boot" process will temporarily eliminate that software conflict.
During a clean boot, the PC restarts without activating its non-Microsoft programs. If the Windows updates can then be installed, one of those inactive programs was causing the interference. In addition, the clean boot process can check those programs to determine which is to blame. Either uninstall that program, or keep it and use the clean boot process each time you get a Windows update. For details, see tinyurl.com/kwrffhg and tinyurl.com/mh5dmyu.
Q: I bought a home built in 1988 that has a whole-house sound system made by M&S Systems. The system sends radio, cassette tape music and intercom service to seven remote speakers. How can I upgrade this system so it will connect to CD players, iPods and smartphones?
Jim O'Brien, Mendota Heights
A: You can't upgrade your old analog system to handle digital inputs. But you can buy a replacement system that will use existing speaker wiring and provide a USB port and Bluetooth wireless capability for connecting to digital music devices. See tinyurl.com/q4smvvw.
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