Do I need a 8-pin ATX12V to unlock X2 555 BE?

[StrangerGuy]

Currently using a 4-pin ATX12V CM 430W PSU...With Gigabyte MA785G-US2H which has an 8-pin ATX12V.

Set EC firmware to hybrid, ACC to auto. The POST displays a Phenom II X4, but was unable to load into Win 7. I was wondering if this chip is really a dud or just not having enough juice...

 

[Axon]

You can bump the juice, but it's a last resort. I have a chip just like that; POSTS bios as an X4 955 but will not load Windows no matter what. I once pushed the CPU voltage to 1.5 and the VCPU-NB to 1.4, but it still hung at the loading screen of Windows.

You can try incrementally bumping the CPU voltage to 1.4 and the VCPU-NB to 1.35 (turn off Cool n Quiet as well), and you can try getting the F3 BIOS from Gigabyte. But ultimately, it sounds like the extra cores are duds man. Sorry.

EDIT: To answer your question, I don't think you need an 8-PIN 12v. I used one on my UD2H but I sincerely doubt it matters. If the board posts and the cores are good, it would boot...

 

[Occ]

Technically, no I don't think so. I unlocked my 720 x3->x4 on a gigabyte board with an 8 pin atx12v, but had an older PSU with only a 4 pin connector. It did have more juice though (Cooler Master 650). Not being able to boot into Windows sounds like the extra cores are bad, not that the CPU isn't getting enough power.