Please help computer will not post

[boomhowar]

My hardware:
ga-ep45-ud3p
q6600
ocz600sxs
hd4850
2 barracuda seagate
ozc 6400 ram


just built computer a week ago and all has been fine for that time. Computer now starts beeps once ("system boots correctly" according to manual) displays the gigabyte screen for about 20 seconds and then reboots. I can not enter bios.

The last thing i did on the computer was enter bios to adjust some settings as i fine tune my overclock. Last settings were 3.2ghz with 1.43vcore and north bridge at 1.1v. My ram was at 2.0v.

I have had about 30 or so unstable overclocks with this system but was able to recover every time from a cmos flash.

Here is what I have tried:

switched cpu with another known working q6600
switched psu with known working 500w antec psu
switched ram with known working patriot ram
switched video card with known working x1950gt
used jumper to flash cmos-left jumper in for 5 minutes
removed cmos battery for 5 minutes

each of the steps above were done individually as i tried to isolate the problem. The only test i could think of to try for the MB was to remove the ram and listen for error beeps which the MB sounded as soon as I tried to boot it with no ram.

Is my MB toast? What else could I try. I'm sending a doa cpu back to newegg tomorrow so if I have a bad MB i'd like to send everything back all in one to save on shipping. Oh, and I tried flashing the cmos first before switching out any components and i disconnected all of my peripherals while i was testing all of the hardware--so no hd, dvd rom, fans or anything was connected to the MB.

Please Help!!! Any input is appreciated.

Thanks

 

[Zecow]

Take out the mobo and test it outside your case. Take out the battery and leave it for 10-20 minutes - let the CMOS clear itself. Put it back in along with 1 stick of ram, cpu, and vga. See if it works.

 

[jitpublisher]

Are you using a USB keyboard?
Have you tried using a standard PS2 keyboard? If you disabled the USB support or turned off the USB keyboard support (which some BIOS's will do by default) you cannot use your USB keyboard. You'll have to hook up a standard keyboard to enter the BIOS and turn these features back on.

 

[boomhowar]

I left cmos battery out of comp overnight and just tried again this morning but same results. I've also pulled the MB from the case and tried to boot with it.

Yea, using PS2 keyboard.

Any other suggestions before I RMA it?

 

[Amg]

check all the jumpers(to the mobo manul) and power conectors and make sure they are in properly