Phenom X3 8450 + Biostar N68S+ ; 2 cores only

Hello
well i have a question, after searching google for hours...
im tired of reading with no certain answers so i might ask for help intead spend more time reading useless post.


i have an amd phenom x3 8450 and a biostar n68s+ motherboard
ive just formated and reinstalled windows 7 x64 bits and now the phenom has only 2 cores working.
(i used to have the 3 cores running with an ECS770M-a motherboard)

device manager shows 2 cores
msconfig option is showin only 2 cores.
cpuz shows 2 cores too.
and cpu z says i have a amd sempron LE-1230

ive upgraded the bios of my MB with no changes for this problem... ive installed all updates for win7...

what should i do to get my 3 f..ng cores?

PLEASE HELP!

I've never heard of this problem before. I had a Phenom X3 8150 in a ASUS M3N78-VM and it was always fine.

I did happen to find this link, not sure if its any help.

Does your BIOS list the CPU as the right model? Does Windows? And can you put up screenshots of the CPUZ main tab, and motherboard tab.