Intel 865 support for Core2Duo

[Curly]

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?

Thanks.

 

[George Macdonald]

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?

BIOS support is obviously important but there's also voltage regulation
which is somewhat different, to fit the Core 2 Duo power profile. You need
to be careful because some mfrs have mbrds which are compatible but only in
the "PCB R2.0" version.

 

[DaveW]

ONLY the later produced 965 and 975 Intel chipsets are compatible with Core
2 Duo.

 

[Tony Hill]

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.

 

[Curly]

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

Do you know whether this 800MT/s processor will be released, or is this
just a maybe?

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.

Oh. Well, I guess that answers my question above. Do you have a link to
this rumored processor(s)?

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.

Thanks Tony, that answered my question perfectly. I was hoping to carry my
AGP All-In-Wonder Radeon to a Core2Duo platform, but I see that there
would be a trade off now. Would you happen to know whether it is
*possible* for there to be AGP on a Intel Core2Duo chipset that supports
1066FSB, or am I wasting my time looking? I'm assuming 945 or 965, and I
don't want anything other than an Intel chipset. I did see a Via [spit]
offering. I also don't like the idea of over clocking from 800 to 1066, as
reliability is more important to me.

Thanks again.

 

[Tony Hill]

Do you know whether this 800MT/s processor will be released, or is this
just a maybe?

Nothing official from Intel yet, just some rumors from the usual
suspects:

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.

Oh. Well, I guess that answers my question above. Do you have a link to
this rumored processor(s)?
http://www.xbitlabs.com/news/cpu/display/20060718232600.html

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.

Thanks Tony, that answered my question perfectly. I was hoping to carry my
AGP All-In-Wonder Radeon to a Core2Duo platform, but I see that there
would be a trade off now. Would you happen to know whether it is
*possible* for there to be AGP on a Intel Core2Duo chipset that supports
1066FSB, or am I wasting my time looking? I'm assuming 945 or 965, and I
don't want anything other than an Intel chipset. I did see a Via [spit]
offering. I also don't like the idea of over clocking from 800 to 1066, as
reliability is more important to me.

It's definitely possible, though not from Intel. As you mention VIA
has done it, as has SiS, but Intel has decided against such a design.
Now, that being said, there are some tricks that you can use. Some
motherboards actually do have an AGP slot on an Intel i9xx series
motherboard:

http://www.anandtech.com/mb/showdoc.html?i=2074

To the best of my knowledge the only ones available used the i915
chipset and therefore do not support Core 2 Duo chips, however there
is no technical reason why the same couldn't be done with an i945 or
i965 chipset. Of course, given that this involves basically turning
your AGP card into a PCI card, it isn't an ideal solution.