Endless reboot problem new motherboard

[elkatman]

Hi, I cannot boot up my new motherboard and cpu even tho I have disconnected everything, including RAM, Graphics card and all drives. The only connections to the motherboard are the ATX and ATX 12V power supplies. When I try to power-up the motherboard the following happens. 1. The CPU cooling fan runs and the onboard LED's all light up for about two seconds. Then everything dies as it powers itself down. 2. After about five seconds, the same thing happens. 3. This cycle continues until I unplug the ATX 12V supply to the CPU, which stops the system from powering down but of course nothing else happens. Can anyone please help me? Thanks. Gigabyte S-Series EP45-DS3L Socket 775 Rev.1.0 Intel P45 Chipset, Intel E8500 Antec 550W.

[TimeDeatH]

not too sure about this but did you ground yourself when you put the cpu in?

[elkatman]

Yes, grounded before installing CPU.

[TimeDeatH]

Well, it almost sounds like your cpu is a deadbolt, are there any other cpu's in your house from like an old dell or hp or something like that? If so install it to the mobo and try booting with that processor. But really a basic lesson in electricity is that if it cant circulate then it cant pass the electricity through. Try reinstalling the cpu.

[elkatman]

Thanks TimedeatH. Will check CPU installation and possible motherboard shorting to case later today. I have the old motherboard with it's pentium IV chip. If that fits the Socket 775 (any idea?) then I will test as you said. Thanks again.

[TimeDeatH]

Wait! Before you do that: You may not have the correct 4 pin power plug coming from the power supply going to the CPU power socket. Some power supplies have two four pin plugs that carry different voltages. They can be easily confused.

[elkatman]

Thanks. I will check that again but I'm pretty sure it right.

[TimeDeatH]

Wow ive been researching your problem and just realized this is like a computer plague with no answer . My best bet is to try everything above, if that doesnt work, replace your power supply with something better, if it still doesnt work, your unfortunately going to have to replace the motherboard.

[RicheemxX]

Back the pony up, first off you need to have at least one stick of ram installed for the board to boot. Second unless you've got on-board video you need to have the gpu installed as well or you'd have no way of knowing its booting or not.

First things first, I'd pull all the parts out of the case and try assembling them on a book or box (any none conductive surface). Add on only the needed parts, CPU, hs/fan, single stick of ram and video card. Check all your power connections, clear the CMOS (use the jumper or pull the battery). I'd go as far as reseating the cpu and heatsink make sure you've got it on there properly.

[elkatman]

thanks, I will try and see what happens. Will let you know in about 12hrs (after work).