Dual CPU motherboards have been around since the Socket 7 days.
They were usually used in servers.
When Intel hit the heat barriar with the Pentium 4 CPU's they had to find a new direction to go in to continue releasing new products.
Using the idea of more is better & seeing that servers use 2 CPU's somebody came up with the idea of a CPU with 2 CPU's on a single chip .
The Pentium D was "born" .
To give their product a facade of truly new technology rather the a variation of the old the term "core" was used to describe 2 CPU's on a single chip.
Refining the technology produced the "dual core" , Core2Duo, & a new generation of "dual core" .
Once Intel hit the heat barriar with the 2 "core" CPU's to keep releasing new products they implemented the "more is better" line of thinking & the "quad core" was born.
[Now that they are getting close to hitting the wall with those they are , once again, implementing the "more is better" line of thinkung & are working on 6 & 8 "core" CPU's
Now to answer.
I have 2 Intel Pentium D 3.40 GHz. And I was wondering if it would be any better to switch to a Intel Core 2 Duo E8400.
That is a bit of a toughy .
With 2 Pentium D 3.40 GHz you actually have 4 CPU's running @ 3.4GHz with a front bus of 800MHz.
With a E8400 you have 2 CPU's running at 3.0GHz with a front bus of 1333MHz.
Given that you would be trading 4 for 2, losing .4GHz , BUT gaining a 1333MHz front bus & the newer techno;ogy , and after refering to this chart,http://www.cpubenchmark.net/cpu_lookup.php...ntium+D+3.46GHz
O would say DEFINATLY go with the E8400 .
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