Motherboard and Power Supply Unit Problems

[wirelessprom]

I'm having an Emachine T2042 2ghz Celeron. I know its the Power Supply cause I took it out and installed my old OCZ 700 watt game ex team and now everything works perfectly. However after I put in my various PCI cards into the motherboard when I started up the computer, it turned on then off. I tried to restart it but when I would cycle the power it wouldn't turn on. I replaced the PSU and am having some problems. I would have to unplug it, plug it back in and then I would get the same result: the fan would spin then it would power down. So, can any body tell me that how do i resolve my Motherboard and Power Supply Unit problems? Does any body knows about it? Kindly help me out to resolve the above issue. Thanks.

[Amd Athlon]

A bad power supply can be the root of many PC problems. While this can also be caused by a faulty switch, it is usually the result of a burned-out power supply. Power Supplies contain dangerous voltages and should only be opened by experienced and qualified engineers, there are no user servicable parts inside. When this component fails, there is simply no activity going on with your computer.

[PeterAGASSI]

If there is power, you will have to open the PC and check for power from the power supply to the motherboard. Power supply is a reference to a source of electrical power. A device or system that supplies electrical or other types of energy to an output load or group of loads is called a power supply unit or PSU. One of the simplest tests you can perform on a power supply is to measure the output voltages. The PSU can cause a myriad of problems and can frustrate computer users who are not use to dealing with this temperamental component.

[Joshua]

When using a multimeter to check voltage, be sure you have a good ground for the black lead of the multimeter. Note that you must check the output voltages while the supply is under a load, which means that it will be installed and running in the PC. If the power doesn't come on, the first thing to check is that you have a live power source. You don't need a DVM (Digital Volt Meter) to check if your power outlet is live.

[Russell]

Another clue is that the system boots, but the system makes rapid, short beeps repeatedly and does not boot. One main problem you may face with an ailing power supply is that it may reboot the computer without any warning. All information is lost and it seems as though this happens at the worst possible time.

[MattyBoy]

If the wall outlet and the power cord are good, make sure the connection at the motherboard is secure. The power supply may fail to operate if the motherboard is not connected to the power supply. Check if all the connectors are plugged in properly. The mains voltage may have dropped a bit due to high demand in the hood, and the standby current that was already weak drops to a level that the mother board cannot recognize. To many pci cards in a system that use the standby voltage eg. wake on LAN nics and some video cards, ps2 mice and keyboards, can drop the voltage to much and stop a pc from powering down or up. This problem can also be caused by a power supply that has a weak standby current.