fresh built comp. won't boot

[Rooster007]

i just built a comp. with an Amptron K7-807 m.b., an AMD duron 800, new 256mb memory, and all the working perifials from another comp. when i turn the power on the atx supply, my power light on the m.b. lights up. then i try and turn the comp. on, it runs for about 30 sec.(never getting to a bios or anything) then all power cuts off and back on agan. even the fan on the power supply cuts off and the m.b. power light. it gets in a loop of off and on untill i kill the power. i unpluged every thing but cpu, memory, and video and it still happens. i pulled the ram out and it still happens. i pulled the video out and it still happens. i pulled the cpu out and the only thing that happend was the power stayd on. befor i return this cpu, could there be something wrong with my M.B.?

 

[edfair]

More likely underpowered PS. What power do you have? Ed Fair
efair@atlnet.com

Any advice I give is my best judgement based on my interpretation of the facts you supply.

Help increase my knowledge by providing some feedback, good or bad, on any advice I have given.

 

[Rooster007]

i'm using a 250w power supply that is just as new as the case and everything els.

 

[tschuy]

There's you problem right there. Power supply is too small. Should be at least 300 WATT or more with the AMD CPU's and motherboards. Plus make sure that the next one you buy is AMD certified

 

[mcvpjd3]

My PC powers 3 CD Drives( CD/CDRW/DVD), a DAT drive, 2 Hard disk, sound card, SCSI card, MPEG card, GeForce 3D card, TV Card, Network Card, USB HID and Modem, AMD T.Bbird 900, Memory, etc... all from a 250Watt PS.

 

[mplack]

I had a simular situation with my AMD Athlon on an ABIT motherboard. Turned out the motherboard was expecting a slower CPU (or was it faster, don't really remember...) and would shut itself down when it didn't find it. I finally found a jumper (referenced in the manual) that I could ground that would reset the motherboard CMOS - that allowed the system to recognize the new CPU and boot. Don't know if that will help or not...

 

[lgebhart]

Is the voltage on the power supply set to 115 and not 240 on the back of the power supply?? ggebhart@clover.net
I hope I never get too old or arrogant to learn something new!

 

[flip31]

Hey there,

This might sound very elementary, but I have had this happen on quite a few occasions. I run Wizard Data Systems and build quite a few computers on a daily basis. I have seen problems with case designs, where the power switch sticks. This will cause this type of problem to. The power will come on the computer for approx, 10-30 seconds, depending on the type of power supply, then shut itself down.

Good Luck.