motherboard powers up then powers right down

[stumpy]

Recently I purchased an ASUS A7V Motherboard and a 900MHz Athlon CPU. I also purchased an Enlight Case and Sony Floppy Drive. TCComputers integrated the chip and the motherboard. I placed the motherboard and chip in the enlight case and connected the floppy drive, a new 40GB Western Digitial Ultra DMA/100 Hard Drive, a new 52X CDROM, and SB Live sound card, and Voodoo3 16MB 3dFx video card, a LinkSYS 10/100 NIC, and an HP CD Writer to the mother board. I also installed one 128 MB DIMM in the appropriate slot. The Hard Drive is connected to the Primary 100 connector and the 2 CD ROM Drives are connected to the secondary IDE connector. After checking and doubling checking all the connectors and jumpers and switches, I am fairly confident that everything is connected to the motherboard properly. Now here's the problem, I connected the keyboard, mouse, monitor and speakers to their appropriate connectors and powered on the system. The system has a 300 watt power supply. The system fans and hard drive spun for about 3-4 seconds and then the system powers down. There is a green powerlight on the motherboard that lights up also, the motherboard manual says this is an indication that the system is on standby or sleep mode . I cannot get past this point to adjust BIOS settings or make any configuration changes. I disconnected some of the hardware to make sure the power supply was sufficient and it does the same thing. TCComputers, integrated the chip (as I stated earlier) so I'm assuming that the system did power up at some point. Is there some jumper setting I'm overlooking or some process to remove the system from stand by if that is indeed the problem? Any help or direction you can give me would be greatly appreciated.

Thank you,

[Paleo Pete]

The PC Guide's Troubleshooting the Boot Process (http://www.pcguide.com/ts/x/boot/quick.htm) might help.

A few things to check:

Try only motherboard, CPU, memory, video card and keyboard, if it works add components one at a time. (The only way to go!) If you have a problem at this point, pull it out of the case and try it on a table to rule out a ground problem.
Be sure all the cables are plugged in and routed correctly.
Make sure the Power supply plug(s) to the motherboard is oriented correctly.
Be sure the CPU is oriented correctly.
Check the memory to be sure it it supported by the motherboard, and try it in another machine to be sure it's good.
Double check all motherboard jumpers, especially CPU voltage, bus speed and multiplier.


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If you had everything...Where would you put it?

Computer Information Links (http://www.geocities.com/paleopete/)

[Rayista Geoff]

Just something else to throw out if Pete's suggestions don't get you any joy. If it *is* the case that the power management settings have gotten screwed up somehow, maybe clearing the CMOS could help, either by removing the battery or setting the CMOS clear jumper. Just a thought.

Geoff

[Matt]

What did you set the "power on by keyboard" jumper to an your motherboard? If you shorted the pins that enable this option does your keyboard and power supply support the 5 volt standby lead that is required? Also, is the keyboard working properly ie. sleep or power key not stuck. If it is powering down after 3-4 seconds you might check the pin connection from the power button on the front of the case to the mother board. Should not be a bad power button itself though since the computer goes into sleep mode instead of shutting down completely.