pc won't boot any more
I built a brand new PC about 2 months ago. It ran without any problems so far. Today, I told Windows XP to turn of the computer, which it did. A bit later I tried to switch the PC back on again, but it wouldn't boot - no fan noise from the power supply or any of the other fans, everything black.
I opened the machine and found the following:
- the power LED on the mainboard is on when power is connected (this is a small status indicator LED on the mainboard that shows that standby voltage is present
- trying to bridge the Powerswitch Jumper on the mainboard with a screwdriver doesn't work
- briding PIN 14 and PIN 15 directly on the ATX plug works, the fans start to spin (cpu cooler as well) and the speaker peeps
- the system won't switch on, even when all harddrives, ram and cards have been removed
- PIN 9 (Standby Voltage) measured with a voltmeter shows 3 Volts, not 5V
- there is not smell of burnt plastic
I admit that the power supply is a rather cheap and nasty one, it's also a ATX1 supply, whereas the mainboard has got a connector for an ATX2 supply (the 4 extra pins, that make the ATX2 plug longer)
Since I built the machine myself I need to be able to correctly identify the broken component before I can bring it back to the retailer.
Does anyone know whether it's more likely that the mainboard is broken or whether the powersupply is broken (despite that fact that it seem to deliver power, albeit 3V instead of 5V on standby voltage).
Thank you for your help.