Problems overclocking Athlon ii X4 640

I am trying to overclock Athlon II x4 640 quad core but no matter how slight of an overclock I give it the computer won't boot. It exits the bios then restarts but the fans and LEDs just turn on for a second then the computer shuts off immediately and I need to clear CMOS and reset the bios to default. Before installing the x4 640 I had the same setup but with an Athlon II x2 245 duel core. I have tried underclocking the ram as well as the northbridge multiple times to see if I could get it to boot but no success cool and quiet is disabled as well.
My exact setup is:

CPU - AMD Athlon II X4 640

Motherboard - ASRock 880GM-LE

Memory - Kingston HyperX FURY 8GB Kit (2x4GB) 1333MHz DDR3 CL9 DIMM

Power Supply - Rosewill Photon-750, PHOTON Series 750W Full Modular Power Supply, 80 PLUS Gold Certified, Single +12V Rail, Intel 4th Gen CPU Ready, SLI & Crossfire Ready

GPU - EVGA Nvidia GeForce GTX 760


I have seen multiple threads about overclocking this processor so I know its possible but I can't even raise the FSB speed up to 205 from 200 and get it to boot.

I have also tried swapping out the ram as well as removing one of the sticks and trying it in both slots separately and I get the same result.
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  1. That is indeed odd. The Athlon II x4s are good OC'ers considering they have a locked multiplier. While that board is not well designed to OC*, it should at least allow a small OC. If you leave everything at default but increase the FSB up to 205, it won't boot?
    Was the CPU or motherboard bought used?

    *No heat sink on the VRMs. 3+1 Phase power.
  2. clutchc said:
    That is indeed odd. The Athlon II x4s are good OC'ers considering they have a locked multiplier. While that board is not well designed to OC*, it should at least allow a small OC. If you leave everything at default but increase the FSB up to 205, it won't boot?
    Was the CPU or motherboard bought used?

    *No heat sink on the VRMs. 3+1 Phase power.


    The cpu was used but the board is new. I have used the board to overclock a duel core Athlon before. The bios lets me adjust the multiplayer but no higher than 15. And I just noticed the voltage is sitting at 1.432v when I look in CPU-Z but in the bios it shows the max voltage at 1.4v which is the top end of what AMD recommends.
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