Old Computer, New Problem

Hello,

I have a problem with my old computer at the office. It doesn't boot at all. I don't see any harddisk activity and the monitor is not activated (stays in standby mode). The mainboard should be recieving electricity because a green light on the mainboard is on. I tought it could be a harddisk problem, but as there is no monitor activity, the 2 likely culprits are the grapics card or the mainboard. If it was the graphics card, I'd expect to see some harddisk activity, but there is none. I don't hear any beeps from the BIOS warning system.

Any ideas on how to proceed?

Thanks

 

Try reseating all your components on the motherboard (RAM. CPU[be rplace thermal paste etc] and GPU) disconnect and reconnect HDs and MB cable and retry. Sometimes this is enough to solve the problem.

If the problem persists take all your components out of the case. place the MB on a non conductive surface such as cardboard. remove all devices except CPU, RAM and GPU (If onboard GPU is not available) and connect to your power supply. connect your monitor and try to boot. Obviously with no HDs etc you wont get to windows but you should get you PC to POST and you can then begin to reconnect devices until it fails. This may identify the faulty component.

Also test your PSU. I feel it is unlikely but it is possible that you aren't getting enough juice to power your system. I found a good guide on how to test here

If it still wont boot the you will have to start swapping core components. Most likely culprit is MB as I believe it is pretty rare for CPUs to fail. Bad RAM would probably result in a load of beeps.

 

Although Tueur has good advice for major diagnostics, I would save time by attempting to test the PC with a new power supply (PSU) before disassembling the entire PC.

If you have a known good PSU that is equal to or greater than the wattage of the currently installed PC, hook it up to the board and drives. If it powers up and boots, your old PSU is the culprit (this should take about 20 minutes, versus 1-2 hours minimum for a disassembly).

A few general notes on PSUs:

* A typical PSU loses 8-10% of its max. output per year of use. As an example, a 4 year old PSU rated at 400 watts may be putting out as little as 250 watts - less or none if it has failed.

* Multimeters or PSU testers are not always accurate since they measure voltage with very little load. This is similar to a car battery: A multimeter hooked to the battery terminals may show 12 volts (no load) although an attempt to draw power under load by hitting the starter results in "click, click, click."

* Given the load factor (above), it's possible the light on the Ethernet port and/or the motherboard may be lit even if the PSU is bad.

* In rare cases, a PSU failure can do damage to the motherboard, drives or other hardware (an over-voltage surge at failure). This is why it's better to spend a few extra bucks on a quality, name-brand PSU that has active power factor correction (Active PFC). ​

Good luck - I hope this solves the problem.

 

Thank you all for these valuable informations. I'll start with the PSU advice and go on from there.

 

Just a couple of suggestions that only take a few minutes each to try:

I recall one old (running W98) PC I used to get called out to every few months or so, it was not used often. All I needed to do was to disconnect all external connections, reconnect them and it worked fine.

A commoner trick that might work: disconnect the machine from power then hold the on button in for about 1 minute, release and reconnect.