Phenom II x4 965 Cant reset FSB from 240 back to Default 200 in BIOS

Hi, hoping somebody can help. I Don't seem to post much, only when I get my self into trouble but it's worked out so far. Heres my problem. I am running an
Athlon II x4 Black Edition 965 cpu with a MSI NF750-G55 AM3 NVIDIA nForce 750a SLI motherboard. There is an overclock switch on the motherboard that has been disabled or turned to off.

http://www.newegg.com/Product/Prod [...] 6813130235
http://www.newegg.com/Product/Prod [...] -_-Product

Here is my problem. I cannot set the stock bus speed in the BIOS back to 200MHz. The lowest it goes is 240. Even at fail safe. I have tried everything disabling cool and quiet and core calibration. This is making the 4th core unstable and giving me blue screens I believe. I have run it as low as 2.4GHz with the bus at 240 and multiplier at around 10 and still blue screens. Usually happens when running multi-threaded applications like extracting files. A Prime 95 test shows an unstable 4th core within seconds. I believe not being able to set the cpu bus speed in BIOS in the culprit. Thanks in advance for any help.

You tried pulling the cmos battery for 5 minutes?

His multiplier is 10 probably because it's cool n quiet. It under-clocks the cpu on it's own.

geekapproved stated this already but....reset the BIOS...pull the CMOS battery for 5 minutes...That should set it all back to defaults...no default is 200 MHz

Ah...+1^ henydiah.....didn't think of that

Aside from yanking out the battery, you can also use the JBAT1 jumper to clear the CMOS. With the system's power off (unplug the P1 and P4 connectors, too), move the jumper so that it covers pins 2-3. Wait for a minute or so, then place the jumper back to it's original position, covering pins 1-2.

Sounds like the easy OC switch itself is broke ...as in, the switch physically moves yet is stuck in the on position...try messing with the easy OC button..like slide to the ON position then slide it to OFF....maybe something is just stuck inside of it that can be jiggled free

I can get it to run at stock settings by unplugging everything and reseting it but in bios I cannot get the fsb down to 200. It will go no lower than 240. So if I save in the bios im screwed.

I dont have any overclocking utilities that run from windows.

When I turn on the pc it tells me the cmos checksum is bad press f1 to enter setup. Then from there I have to hit ESC to boot into windows. If I save any options in the bios it bumps the fsb back up to 240. So I'm stable now but I cannot change a thing in the bios at all.

Too late for that..................

My MSI MB has the same OC switch and I had same problem - drove me insane for months
I come to find out that the 'default' position (read MB manual on MSI website) for the switch is for both to be set towards where it says ON (a$$ backwards MSI) I had them set to the side with the numbers thinking that was off (because the other side says ON) but its not.
I almost threw the comp off the roof over this one. Now shes my bestest friend again :0)
Hope this helps

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