What exactly is the "VRM" rating on motherboards. ie: Phase 10, Phase 18....
I know it has something to do power distribution.
I have a choice between a Phase 10 and Phase 18 boards, not much difference between the two boards other then the VRM, and one is $50 more.
My 2nd question is about "dual lan" boards. I do not see any practical purpose for this, unless its for an office PC or server. Perhaps though with a dual lan setup you could plug another PC directly to another as a simple way of transferring files?
VRM is Voltage Regulation Module, and yes it refers to the power system for the CPU and its memory controller. It's usually given in an "x + y" format, where x is the phases for the CPU and y is the phases for the memory controller and other non-core CPU functions.
Theoretically, the higher the number of phases, the smoother the power delivery will be, and the higher the overclocking potential. Also, each component in the power system will produce less heat as the load is shared between all the phases. In reality, with current processors any board with an 8+2 power system is good. Anything more than that is overkill. I wouldn't pay a $50 premium, but $20 might be worth it.
Some dual-LAN setups can be configured to have the two LAN ports work together to give higher network bandwidth. Other than that, the PC could be connected to two different networks at the same time.