Troubleshooting the hardware of a computer almost always requires removing the computer case covers. Before removing or replacing the covers, the computer power cable should be unplugged. This is not to protect you! It is to protect the computer. It is far easier to damage your computer when power is present and something untoward always seems to happen during these procedures.

Remember that hardware problems are relatively rare and usually obvious. Do not begin troubleshooting with the assumption that your problem is hardware related. If you feel certain you’re problem is hardware related then go ahead. Less obvious hardware problems are usually found by substituting a known good unit for a suspect one. Most of us don’t have spare units (much less known good ones) laying around for this purpose. We have to beg or borrow such units or figure out a workaround. The simplest method is usually to remove all hardware the computer does not require to boot, and then boot the computer. If the problem has gone away, replace the units one at a time; rebooting after each replacement. When the problem comes back you have found the defective unit and can buy a replacement. If the problem has not gone away it is in whatever components remain in the computer. All the computer requires to boot is the power supply, motherboard, memory, a graphics card and boot drive (the boot drive is necessary but should have long since been eliminated as a possible cause). In some computers the graphics capability is built into the motherboard so any problem there becomes a motherboard problem.) At this stage you can do some memory chip swapping if you have multiple memory chips installed. (Usually there won’t be more than two memory modules.) Remove all the memory chips but the first and reboot. If the problem disappears you have a bad memory chip and simply have to repeat the procedure for each memory chip (test in the first slot) until you find the bad one. If it doesn’t fix the problem repeat the procedure for each memory chip until a bad chip is found or the memory is eliminated as the cause. At this stage I think its time to let the professionals determine the actual cause. You’re going to have to replace the malfunctioning assembly in any case.

In actual fact I have doubts about most computer users accurately determining that the problem is in fact a hardware problem and then getting through the evaluation procedure without causing some additional damage. It is certainly well within their capability if they wish to do it. The computer company that I normally deal with (Software Central) has a flat diagnostic fee to check out a malfunctioning computer. (A couple of week ago I was told that this fee was $25 but it should probably be confirmed before having your computer evaluated.) I suspect this might be the best route for most of us, particularly in the case of obscure hardware problems. I don’t know it for a fact but I assume that other local computer companies have a similar arrangement.

There is a situation that buyers of new personal computers (in particular bargain systems) should be aware of.

The reduction in computer prices over the last couple of years has required suppliers to reduce costs to maintain their profit margins. They have done this by reducing quantity, quality, and/or capacity of various components. In particular they have redesigned the power supply units to provide power for the computer as configured at delivery. In addition some are buying them from Asian sources, which do not include the safety margin most American providers would build in as a matter of course. When you power up your computer and the power supply has stabilized it sends a Power Good signal to the computer motherboard. When the motherboard receives this signal it runs the POST procedures and boots the computer. If this signal is lost, even momentarily, the computer will lockup or reboot spontaneously. Overloading the power supply (drawing more current than it was designed to provide) causes problems with the signal. It is not a malfunction in the normal sense but the only cure is to reduce the load or replace the power supply with a higher capacity one.

This does not present a problem unless you upgrade or add to your system. If you do upgrade, particularly to a high performance audio and/or video card, you may find yourself with a system which frequently lockups up or spontaneously reboots. Technically this is not a malfunction. You are simply overloading the power supply. The solution is to reduce the load on the power supply (reverse the upgrade) or more likely include a better power supply as part of your up grade.

CAG