A7V falls asleep during POST

[DJH]

I'm building a new system with the A7V and a Duron 700 MHz CPU. It has 64MB of PC100 RAM, IBM hard drive, Sony CD-ROM and floppy. The power supply is 300 watts. I assembled everything and tried to boot the system. It will run for 4 or 5 second and then goes into sleep or suspend mode. The power LED (not the one on the MB) is blinking. If I hold the power button for a few seconds I can power off the system completely and then restart it. I've tried clearing the CMOS but it didn't help. Sometimes I get the single BEEP of a good POST and sometimes I don't. It won't stay running long enough for me to change anything in the BIOS. Anyone else encounter this problem?

 

[DJH]

Further experimentation leads me to believe I have a defective power supply. The board works fine with a temporary replacement PSU. The original is on its way back to the vendor.