Hi, been reading through this forum for a while but never thought of registering since reading alone is good enough to answer my question. But, today, I've finally come to a question I need to ask, here: Well I'm building a new AM2 system. For now, I've got my X3800+ EE (65W) AM2 processor and is looking for a suitable mobo for it. Looking around and asking those local hardware stores, I've got these few models in mind. Anyway I'm an experienced stock-overclocker so I think you understand. Gigabyte GA-M55S-S3 (nForce 550) Gigabyte GA-M55SLI S4 (nForce4 SLi x8) Gigabyte GA-M57SLI S4 (nForce 570 SLi x8) Reading tells me that the 5xx series motherboard above don't have PCI bus lock. I'm worried about that as I will throw in my Audigy Value with the new board. I don't know about the nForce4 SLi though, any answers/owners can tell me? Don't mind about price tag, I've got the cash, but please don't shoot farer than those 3 listed please. I've got my own reasons. Actually, the M55S-S3 can be removed from the list but I put it there in case any of you got advices on it. Additional questions: Will the nForce4 SLi differ a lot from the nForce5 SLi in performance (ignore features)? Is the M55SLi a good overclocking board? Thanks for reading.