Hi, I have a AMD Phenom II x2 550 that i would like to unlock to 4 cores. My motherboard should support this feature but when i enable ˝Unlock cpu core˝ in BIOS, pc won't boot. It turns on cooling fans and power led, but i don't get anything on screen. I tried enabling ˝CPU Active Core Control˝ but no help. I also tried to raise the CPU voltage a little bit but it doesn't help. Please help! 
Pc specs:
CPU: AMD Phenom II X2 550, OC to 3.4Ghz
Motherboard: ASRock N68-GS3 UCC, BIOS version P1.40
Memory: 4Gb DDR3 Kingston
Graphics card: Sapphire Radeon HD 6770 1Gb, Flex edition
PSU: 500W
Windows: Microsoft Windows 7 64 Bit
Pc specs:
CPU: AMD Phenom II X2 550, OC to 3.4Ghz
Motherboard: ASRock N68-GS3 UCC, BIOS version P1.40
Memory: 4Gb DDR3 Kingston
Graphics card: Sapphire Radeon HD 6770 1Gb, Flex edition
PSU: 500W
Windows: Microsoft Windows 7 64 Bit
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