| Why? Well two channels of RAM really are faster, but the bottleneck becomes the FSB, not the RAM!
Remember that the P4 is using a quad pumped bus running at 100/133MHz, and the Athlon is using a dual pumped bus running at 100/133/166MHz.
Hence, adding another stick of RAM to a P4 system makes a difference, as the FSB is running at least twice as fast as the RAM!
On the Athlon system, the RAM is operating at the same speed as the FSB, so no huge benefits. Strange however, that the Athlon can still keep up with the P4.
Even stranger how Alpha machines equipped with PC100 RAM can outrun P4/Athlon machines with DDR400 RAM.
As always, faster memory does not necessarily translate into faster processing.
Also, the methods that benchmark programs use to measure the bandwidth doesn't often occur in the real world, so the real world benefit of running two channel is lower than the benchmarks would indicate.
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