new motherboard install

[jollyFE]

Hello all, got a problem that has me scratching my head.  I have built several PCs in the past and all have pretty much gone off without a hitch.  This on, I just replaced the motherboard, used all the other parts that worked with the old motherboard.  Now when I press the power button, the case and vid card fans spin for a second and then stop and the pc never boots.  Just a second of fans spinning then nothing.  I have gone over all the connections and everything is where it should be.  Is the board possible grounding out?


Tim

[38ruk]

Why did you change boards? Did the old one die on you ? No beep codes i take it? 

I would pull it out of the case and reseat the cpu and memory ....check the cpu or socket for bent pins (depends on how old and brand on which to check)   then run it with just the video card , cpu and memory on the bench to rule out any grounding .  Just jump the power pins on the header with a screw driver to get it to start ....then go from there.  .

I've lost cpu's in the past and thats what would happen ....mine were usually due to high overclocks ...but when I toasted a cpu the pc would start and instantly shut down. 

[Bizman]

Some motherboards won't run unless the cpu fan has been connected to the right connector. I've seen some with two power connectors side by side with only minuscule markings below them telling which is which. Some won't run without both cpu and case fans are connected. RTFM, it might give a hint if that were the culprit.

[jollyFE]

Everybody is hooked up where they should be, I'll check the seating of the cpu.

[Nath[BDP]]

sounds like a power connector issue to the mobo, but you said you checked it all

[MrRiplEy[H]]

There's always the chance of getting a new part thats DOA or you zapped it with ESD accidentally while installing it. Did you wear a grounding wristband during the install? As a minimum whenever you handle computer components, always first ground yourself to the computer case and only after that touch any part inside (or a new part). It's usually enough to touch the metal of the case if you don't have a proper grounding device.

As others said the problem actually sounds a lot like you forgot to install the 4-pin extra power plug to your motherboard. It's easy to overlook once you plug in the big connector. Other things to check for are CPU cooler, is it plugged in to the correct header - the mobo might shut off immediately when it detects no cpu fan is present to protect your hardware.

If none of the above apply, next thing is try to reset CMOS by removing the battery for a couple of seconds. Then if that won't work, remove _every_ component except the cpu, cpu fan, 1 memory stick and the VGA card (even that should be left off if you have built in graphics option). Then try booting barebones. If it starts to boot start adding devices one by one until you hit the trouble.

Are you sure your motherboard and its bios/uefi supports the cpu you're using?

Take a photo of your motherboard (with all the stuff installed) and post it, perhaps that gives clues.