OK, now I'm a bit confused... I thought a requirement for Core2Duo was a
965 chipset?
http://www.asrock.com/product/775i65G.htm This motherboard
(allegedly) supports them, yet is 865 based.
I guess my question is: What are the requirements for Core2Duo? Is it any
LGA775 board that has BIOS support? Will a 915 chipset support them, if it
has BIOS support?
There are a several pieces that are required for a chipset to support
Core 2 Duo chips:
1. Obviously it needs to support LGA775 sockets and the P4 bus
2. It needs to support a 1066MT/s bus speed, possibly only 800MT/s for
some as-yet unreleased low-end Core 2 Duo chips
3. BIOS support
4. Voltage support
5. Dual-processor support
Now, the i865 chipset CAN meet all those criteria except for the
1066MT/s bus speed. A motherboard can be built with this chipset to
support the unconfirmed future low-end Core 2 Duo chips with only
800MT/s bus speeds, but it can not officially support any of the
current chips. The above-mentioned board gets around this by
overclocking the bus speed on the chipsets, and does so with some
small print about how the integrated graphics won't work in this
setup.
The i915 chipset, on the other hand, fails due to the last
requirement. In a bit of an odd move, Intel deicded to disable
multiprocessor support on their i915 and i925 chipsets. Presumably
this was because they didn't want server vendors selling
dual-processor Xeon servers with low-cost i915 chipsets instead of the
high-cost E5000-series chipsets. Unofortunately this was quite a
short-sighted move, since it meant that these chipsets also couldn't
be used with any dual-core processors, since Intel's shared bus design
basically treats dual-core processors as two separate chips that just
happen to be on the same die. This feature was re-introduced in the
i945 chipsets (which can also support Core2Duo, though some versions
of the chipset lack 1066MT/s bus speed support), and of course the new
i965 chipsets.
In any case, Intel does not officially support Core2Duo chips on the
i865, but the chipset CAN be made to (kinda-sorta) work. Note that
virtualy NO old i865 boards will work with the chips, only ones made
in the past few months. A BIOS upgrade will NOT do the trick, the
board pretty much had to be built with the Core2Duo in mind.