Quoted exactly from Xbitlabs:
"Given that the launches of Intel Conroe central processing units (CPUs) and Intel 965 chipset series seem to be aligned, it is highly probably that the forthcoming mainboards will support the forthcoming processors. The status of Conroe support by currently available mainboards is not that obvious. It looks like today?s mainboards, even those built on the latest Intel 975X chipset, will not be compatible with the upcoming processors known as Conroe. Nonetheless, Intel seem to have no plans to release a new high-end core-logic in the middle of the year, thus, the chipset that is to support possible high-speed Conroe processors is the Intel 975X. That said, there seem to be no actual compatibility issues between the Conroe processors and the Intel 975X chipset: the problem lies with the mainboards.
According to several mainboard manufacturers, the platforms designed to support Conroe processors will feature a new type of Voltage Regulation Module (VRM) onboard. In other words, one the same mainboard on Intel 975X chipset may have different VRM depending on the mainboard revision. Note that one revision will support only Pentium 4 and Pentium D processors and another will also support Conroe processors. It looks like the mainboard voltage regulator should be adapted for stable work with Conroe processors that can support lower voltages and have smaller voltage adjustment increments. The modified mainboards will work fine with the previous generation CPUs as well as with the upcoming Conroe based CPUs. The new VRM should be more universal from this standpoint."
Revision 3.04 and later have the new VRM