PC hardware--CPU & Motherboard & RAM/PC won't turn on.


Hello Mr. Agudelo,

 I have a used desktop computer running WindowsXP Pro with service pack 3 installed.  The motherboard is from Asus and has a Intel Pentium 4 3.0 Ghz CPU with a heatsink and working fan.  I have installed Norton 360 on the machine and it was working fine for about a month.  I turned the computer on one day and it wouldn't start.  The rear case fan only rotated half of one revolution and stopped.  There is one little light on the motherboard that is lit.  I thought it was the power supply was the problem but it apparently isn't.  I also remember that my Norton 360 program warned me previously thet the CPU was running at over 78% capacity multiple times while surfing the web.  Many times, also observed the CPU stuck at 100% in the task manager performance tab. My PC would eventually start after I had left it alone for awhile.  Now,it refuses to start at all.  While I am not 100% sure, I feel this is a hardware problem and I feel it is either the motherboard or the CPU.  I know that you cannot be 100% sure either without physically checking the PC yourself but I would like to ask if theis sounds more like a CPU issue or a motherboard issue?  What can I do to further rule out the motherboard as the problem since it will be more expensive to replace?  The CPU was not overclocked and  while the PC is a relatively old model, it has many quality internal components and I would like to keep it running without breaking the bank. The Norton 360 never warned me previously about any other component except the CPU.  Should I just replace the CPU?

Hi David,

While I agree with you that it looks like a hardware problem, I would disregard the Norton360 message. CPUs used to fail by overheating, but reaching 100% load rarely make it happen. As you mention the CPU was not overclocked, then I would discard the CPU as probable source of the failure.
To me it looks like a motherboard problem and most likely a failed condenser. If you're hardware troubleshoooting inclined, having a close look to the MB may show a leaking condenser. Replacing it might be a challenge, but by far cheaper than any other solution.
If hardware repairs are not your cup of tea, I would look for either a CPU/MB/RAM upgrade, or a totally new computer, depending on your budget.
I don't know if it's available in your area, but used out-of-lease computers might be an interesting option to consider. Just saw in a local re-sale HW store an i7 Core PC with 8GB RAM and 500 GB HDD for under $500, which currently is what you might be looking to fork in for a low tier computer or a mid-tier CPU/MB/RAM upgrade.

Hope it helps,

PC hardware--CPU & Motherboard & RAM

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Ricardo Agudelo


any question on networking area,specially if it`s about Windows based networks. Also, as we do some software and hardware testing here,we can provide some help on the PC problems and repair. In PC communications and Internet access and use. Electronic Engineer,Experience 18 years in telecommunications, control, computers and networks

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