Help with new cpu/mobo...keeps shutting off on it's own

[mogbert]

Hi, didnt know where to post this so i'll post it here and in motherboards. I just got my 2500+ and the A7N8X deluxe and put it all together and fired it up, went into the bios and it just shut down on me. Now whenever I try booting up, it powers on for about 5-10 seconds then just powers down. Before I rma the mobo, does anyone have any suggestions as to what the problem is? No beeps, just on and off. I even removed everything except ram, and cpu and it did exactly the same thing.

Btw here's my specs

Antec 400 psu
A7N8X Deluxe
2 sticks of pc2700 ram
2500+

dunno if anything else would be relevant, any help appreciated, thanks.

 

[TheCorm]

Do you have an alternate CPU you can try? Does it beep if you try and run it up without CPU and/or without RAM? AGP seated correctly? try re-seating it.

 

[shootinyou]

Could also be heat related, check to make sure you have the HSF installed correctly.
looking at a picture of your board, the notch in the HSF should be facing toward the top
of the board.

Edit; Make sure the jumpers are set correctly as well.

 

[mogbert]

Thanks, I dont know why I didnt think about trying my other cpu. I'll try what both of you suggested.

 

[spambot]

Simple question but is the fan moving when you turn the PC on? It's an easier test that looking at pin orientations and I've had a few crappy fans myself.

 

[mogbert]

yup, the fan goes on for about 10 seconds and then shuts down with everything else.

 

[mogbert]

So it turns out the HSF was installed backwards. Thanks to everyone that helped!

 

[TheeeChosenOne]

I had this same exact problem with a similar related chipped mobo.

The KEY is that you must CONNECT the 12v (rather large 4 pin) power connector from your power supply to the mobo in addition to the ATX Power connector.

With both power connectors from the Power Supply feeding into the mobo, your system won't bug out and will boot correctly.

My old mobos only used the main Power Connector, but it seems many of these new ones use 2 nowadays.

Hope this helps.

 

[elzmaddy]

I've never seen a second power connector on a motherboard. Could anyone show me what it looks like, or a mb model that has it?

 

[TheeeChosenOne]

It's a 12 volt plug that most all Power Supplies carry. It has 4 female prongs with a plastic clip like it's larger, wider sibling Power Plug