Originally posted by: Nitetrain
I've searched and noticed that there seem to be some core 2 duos that were offered for the socket 478?
There were not. What you are seeing are Core Duos (no "2", they came before the Core 2 Duo) intended for laptops, which used a socket that had 478 pins. However, their socket (known as Socket M) was not compatible with the desktop socket.
What would be the best processor to use in this 865PE board?
It depends on your definition of "best". AFAICT you can probably run any of the Northwood Pentium 4s and most of the Prescott Pentium 4s, which ran up to 3.8 GHz (the 670 and 672). There are some indications that you can only go up to 3.4 GHz with that chipset; consult the documentation available from your motherboard manufacturer.
In any case, I would imagine the top-end parts are horribly expensive. My suggestion would be to buy something more modest, or start saving up for a motherboard upgrade. Moving to Socket T and a Core 2 Duo or Core 2 Quad would be a large speed improvement over most any Socket 478 part, even assuming you buy one of the older, cheaper processors.
Originally posted by: heyheybooboo
The ""Core Duo"" procs were s478 - AFAIK they were all mobile varieties - Pentium Ms or ""Yonah core""
The Pentium M predates the Core Duo series. All Core Duos (and Core Solos) use the Yonah core. All of these series used 478-pin sockets ("Socket 479" for Pentium M, "Socket M" for Core Duo/Solo), but were not physically compatible with Socket 478 and were not electrically compatible with each other.
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